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Is Ketone An Acid Or Base

Urine Test Types: Ph, Ketones, Proteins, And Cells

Urine Test Types: Ph, Ketones, Proteins, And Cells

Urine as a Diagnostic Tool A long time ago, disgusting as it may be, people used to actually taste and drink urine in order to try and diagnose a patient's disease! I'm not even kidding you. Thankfully, modern-day doctors do not have to resort to such disgusting and even dangerous methods. One of the reasons the doctor barbers of yesteryear used to drink their patient's urine was to see if it had a sweet taste, often indicative of diabetes mellitus. Finding the sweet-tasting glucose in the urine was covered in detail in another lesson, so we'll focus on other important measurements here instead. Interpreting Urine pH One value that can be measured in the urine is known as urine pH. pH is a measure of the acidity or alkalinity of a substance. If the pH is low, then it is acidic. If the pH is high, then it is basic, or alkaline. To remember which is which, I'll give you a little trick that has worked for me. If you grew up watching cartoons, you probably saw some comical ones where cartoonish robbers poured acid on the roof of a bank vault and waited while the acid ate its way downward into the vault, so the robbers could get down there to steal all the cash. If you can recall that acid likes to eat its way downward into things, then you'll remember that acidic substances go down the pH scale. That is to say, their pH numbers are lower than basic substances. Normal urine pH is roughly 4.6-8, with an average of 6. Urine pH can increase, meaning it will become more basic, or alkaline, due to: A urinary tract infection Kidney failure The administration of certain drugs such as sodium bicarbonate Vegetarian diets On the flip side, causes for a decreased, or acidic, urine pH, include: Metabolic or respiratory acidosis Diabetic ketoacidosis, a complication of diabetes mellitus Continue reading >>

Ketone

Ketone

Ketone, any of a class of organic compounds characterized by the presence of a carbonyl group in which the carbon atom is covalently bonded to an oxygen atom. The remaining two bonds are to other carbon atoms or hydrocarbon radicals (R): Ketone compounds have important physiological properties. They are found in several sugars and in compounds for medicinal use, including natural and synthetic steroid hormones. Molecules of the anti-inflammatory agent cortisone contain three ketone groups. Only a small number of ketones are manufactured on a large scale in industry. They can be synthesized by a wide variety of methods, and because of their ease of preparation, relative stability, and high reactivity, they are nearly ideal chemical intermediates. Many complex organic compounds are synthesized using ketones as building blocks. They are most widely used as solvents, especially in industries manufacturing explosives, lacquers, paints, and textiles. Ketones are also used in tanning, as preservatives, and in hydraulic fluids. The most important ketone is acetone (CH3COCH3), a liquid with a sweetish odour. Acetone is one of the few organic compounds that is infinitely soluble in water (i.e., soluble in all proportions); it also dissolves many organic compounds. For this reason—and because of its low boiling point (56 °C [132.8 °F]), which makes it easy to remove by evaporation when no longer wanted—it is one of the most important industrial solvents, being used in such products as paints, varnishes, resins, coatings, and nail-polish removers. The International Union of Pure and Applied Chemistry (IUPAC) name of a ketone is derived by selecting as the parent the longest chain of carbon atoms that contains the carbonyl group. The parent chain is numbered from the end that Continue reading >>

Acid And Base Catalyzed Formation Of Hydrates And Hemiacetals

Acid And Base Catalyzed Formation Of Hydrates And Hemiacetals

Voiceover: We've already seen how to form hydrates and hemiacetals in un-catalyzed reactions; in this video, we're going to see how to form hydrates and hemiacetals, in both acid and base-catalyzed versions. And so, we'll start with the acid-catalyzed: So here we have an aldehyde, or a ketone, and let's do hydration first. So, we know that in a normal hydration reaction, you just have to add water, but in an acid-catalyzed version, you would have to add a proton source, so H plus, and so you'd form hydronium, or H three O plus. And so, in an acid-catalyzed reaction, the first thing that's gonna happen is protonation of your carbonyl oxygen. So, lone pair of electrons on your oxygen here, are gonna pick up a proton from hydronium, leaving these electrons behind, here. So let's go ahead and show what happens: So we're going to protonate the carbonyl oxygen here, so we're gonna have a hydrogen attached, and give this a plus one formal charge, on our oxygen now. Our carbon is still bonded to an R group, and a hydrogen over here, and so, we could draw a resonance structure for this; we could show these pi electrons here, moving off, onto the oxygen, so let's go ahead and do that. So now, this top oxygen here would have two lone pairs of electrons around it, and we took a bond away from this carbon, so if we took a bond away from this carbon, we get a plus one formal charge. So let's go ahead, and put resonance brackets in here, and then, let's follow those electrons. So these pi electrons in here, move out onto that top oxygen, taking a bond away from your carbonyl carbon right here; that's gonna give it a full positive charge in this resonance structure, so plus one formal charge. And so, this makes your carbonyl carbon more electrophilic, which means a nucleophile can atta Continue reading >>

Aldol Condensation – Acid Catalyzed

Aldol Condensation – Acid Catalyzed

Aldol condensation reaction can be either acid catalyzed or base catalyzed. This page deals with the acid catalysis mechanism of the aldol reaction. Earlier, this reaction was thought to occur only with aldehydes. However, it has been realized that a similar reaction would occur with ketones and reactive carbonyl compounds with available α-hydrogens (the need for which will be apparent with the mechanism below). The reaction proceeds with the condensation of an aldehyde (or carbonyl compound) with an enol. The product formed has an aldehyde (or carbonyl) group and a β-hydroxy (alcohol) group, giving the product the name aldol (or if the carbonyl compound is a ketone it maybe called a ketol). This condensation is often followed by spontaneous dehydration due to β-elimination to produce an α,β-unsaturated aldehyde or α,β-unsaturated ketone. The mechanisms for acid catalyzed aldol condensation and base catalyzed aldol condensation is significantly different. While bases activate the nucleophile, acids activate the electrophile in the reaction. It must be noted that aldol condensation is an integral mechanism of Robinson annulation as well. Mechanism of Acid Catalyzed Aldol Condensation Step 1 In step 1 of the reaction, the acid acts as a proton donor and activates the carbonyl oxygen into a protonated form. Step 2 In step 2, the intermediate 1 reacts with the conjugate base of the acid (i.e. A-) to produce the enol (intermediate 2). Step 3 This step involves the conjugation of the enol (intermediate 2) with another molecule of the activated carbonyl compound (intermediate 1) to produce the aldol (or ketol). Step 4 In step 4, the aldol (or ketol) undergoes spontaneous dehydration due to base catalyzed dehydration to yield the α,β-unsaturated aldehyde or α,β-unsat Continue reading >>

Enolization Of Aldehydes And Ketones: Structural Effects On Concerted Acid−base Catalysis

Enolization Of Aldehydes And Ketones: Structural Effects On Concerted Acid−base Catalysis

Abstract The third-order term (kAB) for the concerted acid−base catalyzed enolization of a selection of simple aldehydes and ketones has been measured in a series of substituted acetic acids at 25 °C at constant ionic strength 2.0 (NaNO3). While there is no direct correlation of the magnitude of the third-order term with either the rate constants for acid (kA) or base (kB) catalysis, a simple log−log relationship exists between the product of the consecutive rate constants (kA·kB) and the concerted (third order) rate constants (kAB). This implies that the concerted pathway is important only when both the general acid and the general base terms are significant; this will be useful in designing other systems which might show such concerted catalysis. In the case of aldehydes, a slope of 0.97 was found for this plot, which compares to the result for 4-substituted cyclohexanones (0.51) and other ketones (0.59), as measured in acetic acid buffers. The resultant Brønsted βAB value of 0.20 found for propanal (2) is consistent with the overall observation that concerted catalysis is largely independent of the buffering species, and that process is overall base catalyzed. The solvent isotope effect on the concerted acid−base catalyzed enolization rate term, kAB(H2O)/kAB(D2O) = 1.33, indicates that the transition state for proton transfer to the carbonyl is more advanced than in the case of ketones. In general we have found that carbonyl compounds with large measured (or estimated) enol contents show significant third-order terms. Continue reading >>

Reactive Group Datasheet

Reactive Group Datasheet

Many low-molecular-weight ketones (such as acetone and methyl ethyl ketone) are highly flammable. Most ketones are liquids with relatively high vapor pressures, capable of forming explosive mixtures with air. Materials in this group are reactive with many acids and bases liberating heat and flammable gases (e.g., H2 from NaH). The amount of heat may be sufficient to start a fire in the unreacted portion of the ketone. Ketones react with reducing agents such as hydrides, alkali metals, and nitrides to produce flammable gas (H2) and heat. Ketones are incompatible with isocyanates, aldehydes, cyanides, peroxides, and anhydrides. They react violently with HNO3, HNO3 + H2O2, and HClO4. Varies very widely. Some ketones are highly volatile and may have narcotic or anesthetic effects. Entry into the body occurs by absorption through the skin as well as inhalation and ingestion. Compounds in this group are characterized by a carbonyl attached to two organic groups. These groups may be alkyl (paraffins) or aryl (aromatic). Reactions of this group are very similar in their behavior to that of aldehydes, because of their similar structure. These materials are generally used as solvents in the paint, textiles, plastics, and lacquer industries. 2-tridecanone, acetone, acetophenone, benzoin, cyclohexanone, isophorone, methyl acetone, methyl amyl ketone, methyl butanone, methyl ethyl ketone, ninhydrin. Continue reading >>

The Alkaline Diet Vs Acidic Ketones

The Alkaline Diet Vs Acidic Ketones

Whether you think eating alkaline foods is useful or woo woo junk it appears that metabolic acidosis is a thing. Metabolic acidosis seems to be interrelated with insulin resistance, Type 2 Diabetes, and retention of muscle mass. To prevent metabolic acidosis, it appears prudent to ensure that your body has adequate minerals to enable your kidneys to balance pH over the long term. This can be achieved by eating plenty of veggies and/or supplementing with alkaline minerals (e.g. magnesium, sodium, potassium, zinc etc). If you eat plenty of veggies you’re probably getting enough alkalising minerals, however, you can easily test your urine to see if your dietary acid load is high. If you are targeting a high fat therapeutic ketogenic diet, following a zero-carb dietary approach and/or taking exogenous ketones it seems then it may be even more important to be mindful of your acid load and consider mineral supplementation. Recently I had a fascinating, surprising and exciting experience during a fast. The chart below shows my ketones, glucose and ‘total energy’ (i.e. glucose plus ketones) over the seven days. My ketones increased to above 8.0 mmol/L. They even couldn’t be read on my ketone metre! It was the full keto brochure experience. It was like my body fat was effortlessly feeding my brain with delicious, succulent ketones! I felt great. This chart shows my glucose : ketone index (GKI) dropping to below 0.5 after a few days. The orange dots in this chart shows the relationship between glucose and ketones about 18 months ago when I first started trying this keto thing (after I read ‘Jimmy’s Moore’s Keto Clarity’). The blue dots show the relationship between my glucose and ketones during the recent fast. As you can see from the much flatter line, my blood g Continue reading >>

Ketone

Ketone

Not to be confused with ketone bodies. Ketone group Acetone In chemistry, a ketone (alkanone) /ˈkiːtoʊn/ is an organic compound with the structure RC(=O)R', where R and R' can be a variety of carbon-containing substituents. Ketones and aldehydes are simple compounds that contain a carbonyl group (a carbon-oxygen double bond). They are considered "simple" because they do not have reactive groups like −OH or −Cl attached directly to the carbon atom in the carbonyl group, as in carboxylic acids containing −COOH.[1] Many ketones are known and many are of great importance in industry and in biology. Examples include many sugars (ketoses) and the industrial solvent acetone, which is the smallest ketone. Nomenclature and etymology[edit] The word ketone is derived from Aketon, an old German word for acetone.[2][3] According to the rules of IUPAC nomenclature, ketones are named by changing the suffix -ane of the parent alkane to -anone. The position of the carbonyl group is usually denoted by a number. For the most important ketones, however, traditional nonsystematic names are still generally used, for example acetone and benzophenone. These nonsystematic names are considered retained IUPAC names,[4] although some introductory chemistry textbooks use systematic names such as "2-propanone" or "propan-2-one" for the simplest ketone (CH3−CO−CH3) instead of "acetone". The common names of ketones are obtained by writing separately the names of the two alkyl groups attached to the carbonyl group, followed by "ketone" as a separate word. The names of the alkyl groups are written alphabetically. When the two alkyl groups are the same, the prefix di- is added before the name of alkyl group. The positions of other groups are indicated by Greek letters, the α-carbon being th Continue reading >>

Chapter 16: Aldehydes And Ketones (carbonyl Compounds)

Chapter 16: Aldehydes And Ketones (carbonyl Compounds)

The Carbonyl Double Bond Both the carbon and oxygen atoms are hybridized sp2, so the system is planar. The three oxygen sp2 AO’s are involved as follows: The two unshared electorn pairs of oxygen occupy two of these AO’s, and the third is involved in sigma bond formation to the carbonyl carbon. The three sp2 AO’s on the carbonyl carbon are involved as follows: One of them is involved in sigma bonding to one of the oxygen sp2 AO’s, and the other two are involved in bonding to the R substituents. The 2pz AO’s on oxygen and the carbonyl carbon are involved in pi overlap, forming a pi bond. The pi BMO, formed by positive overlap of the 2p orbitals, has a larger concentration of electron density on oxygen than carbon, because the electrons in this orbital are drawn to the more electronegative atom, where they are more highly stabilized. This result is reversed in the vacant antibonding MO. As a consequence of the distribution in the BMO, the pi bond (as is the case also with the sigma bond) is highly polar, with the negative end of the dipole on oxygen and the positive end on carbon. We will see that this polarity, which is absent in a carbon-carbon pi bond, has the effect of strongly stabilizing the C=O moiety. Resonance Treatment of the Carbonyl Pi Bond 1.Note that the ionic structure (the one on the right side) has one less covalent bond, but this latter is replaced with an ionic bond (electrostatic bond). 2.This structure is a relatively “good” one, therefore, and contributes extensively to the resonance hybrid, making this bond much more thermodynamically stable than the C=C pi bond, for which the corresponding ionic structure is much less favorable (negative charge is less stable on carbon than on oxygen). 3.The carbonyl carbon therefore has extensive car Continue reading >>

Acidity Of

Acidity Of

a-Hydrogens In the following table, the acidity of the H for various enolate systems and other closely related systems are given. You should be able to justify the trends in this data ! Why are the protons adjacent to carbonyl groups acidic ? As we have advocated before, look at the stabilisation of the conjugate base. Notice the proximity of the adjacent p system, and hence the possibility for RESONANCE stabilisation by delocalisation of the negative charge to the more electronegative oxygen atom. The more effective the resonance stabilisation of the negative charge, the more stable the conjugate base is and therefore the more acidic the parent system. Let's compare pKa of the common systems: aldehyde pKa = 17, ketone pKa = 19 and an ester pKa = 25, and try to justify the trend. The difference between the 3 systems is in the nature of the group attached to the common carbonyl. The aldehyde has a hydrogen, the ketone an alkyl- group and the ester an alkoxy- group. H atoms are regarded as having no electronic effect : they don't withdraw or donate electrons. Alkyl groups are weakly electron donating, they tend to destabilise anions (you should recall that they stabilise carbocations). This is because they will be "pushing" electrons towards a negative system which is unfavourable electrostatically. Hence, the anion of a ketone, where there are extra alkyl groups is less stable than that of an aldehyde, and so, a ketone is less acidic. In the ester, there is also a resonance donation from the alkoxy group towards the carbonyl that competes with the stabilisation of the enolate charge. This makes the ester enolate less stable than those of aldehydes and ketones so esters are even less acidic. The most important reactions of ester enolates are the Claisen and Dieckmann cond Continue reading >>

1. Nomenclature Of Aldehydes And Ketones

1. Nomenclature Of Aldehydes And Ketones

Aldehydes and ketones are organic compounds which incorporate a carbonyl functional group, C=O. The carbon atom of this group has two remaining bonds that may be occupied by hydrogen or alkyl or aryl substituents. If at least one of these substituents is hydrogen, the compound is an aldehyde. If neither is hydrogen, the compound is a ketone. The IUPAC system of nomenclature assigns a characteristic suffix to these classes, al to aldehydes and one to ketones. For example, H2C=O is methanal, more commonly called formaldehyde. Since an aldehyde carbonyl group must always lie at the end of a carbon chain, it is by default position #1, and therefore defines the numbering direction. A ketone carbonyl function may be located anywhere within a chain or ring, and its position is given by a locator number. Chain numbering normally starts from the end nearest the carbonyl group. In cyclic ketones the carbonyl group is assigned position #1, and this number is not cited in the name, unless more than one carbonyl group is present. If you are uncertain about the IUPAC rules for nomenclature you should review them now. Examples of IUPAC names are provided (in blue) in the following diagram. Common names are in red, and derived names in black. In common names carbon atoms near the carbonyl group are often designated by Greek letters. The atom adjacent to the function is alpha, the next removed is beta and so on. Since ketones have two sets of neighboring atoms, one set is labeled α, β etc., and the other α', β' etc. Very simple ketones, such as propanone and phenylethanone (first two examples in the right column), do not require a locator number, since there is only one possible site for a ketone carbonyl function. Likewise, locator numbers are omitted for the simple dialdehyde at t Continue reading >>

Reactions At The Α-carbon

Reactions At The Α-carbon

Many aldehydes and ketones undergo substitution reactions at an alpha carbon, as shown in the following diagram (alpha-carbon atoms are colored blue). These reactions are acid or base catalyzed, but in the case of halogenation the reaction generates an acid as one of the products, and is therefore autocatalytic. If the alpha-carbon is a chiral center, as in the second example, the products of halogenation and isotopic exchange are racemic. Indeed, treatment of this ketone reactant with acid or base alone serves to racemize it. Not all carbonyl compounds exhibit these characteristics, the third ketone being an example. Two important conclusions may be drawn from these examples. First, these substitutions are limited to carbon atoms alpha to the carbonyl group. Cyclohexanone (the first ketone) has two alpha-carbons and four potential substitutions (the alpha-hydrogens). Depending on the reaction conditions, one or all four of these hydrogens may be substituted, but none of the remaining six hydrogens on the ring react. The second ketone confirms this fact, only the alpha-carbon undergoing substitution, despite the presence of many other sites. Second, the substitutions are limited to hydrogen atoms. This is demonstrated convincingly by the third ketone, which is structurally similar to the second but has no alpha-hydrogen. 1. Mechanism of Electrophilic α-Substitution Kinetic studies of these reactions provide additional information. The rates of halogenation and isotope exchange are essentially the same (assuming similar catalysts and concentrations), and are identical to the rate of racemization for those reactants having chiral alpha-carbon units. At low to moderate halogen concentrations, the rate of halogen substitution is proportional (i.e. first order) to aldehyde Continue reading >>

A New Class Of “electro-acid/base”-induced Reversible Methyl Ketone Colour Switches

A New Class Of “electro-acid/base”-induced Reversible Methyl Ketone Colour Switches

Methyl ketone has been designed as a switching unit for electrically addressable molecular colour switches. A newly proposed mechanism of “electro-acid/base” (radical ions)-induced intermolecular proton transfer for the colour switch is proven clearly by cyclic voltammetry (CV), X-ray photoelectron spectroscopy (XPS), infrared spectroscopy (IR) and in situ UV-Vis spectroscopy. A dramatic spectral absorption shift (about 291 nm) is observed during the switching, and blue, yellow and green colours are obtained by adjusting the substituents on the methyl ketone-bridged unit. The in situ “electro-acid/base” is far more convenient than the conventional chemical stimulus of acids or bases for the manipulation of the molecular switching properties. This new switching method and molecular structure manipulation will inspire and accelerate the further development of broad switching materials and applications in ultrathin flexible displays, etc. Continue reading >>

Aldehydes And Ketones

Aldehydes And Ketones

Introduction We will focus more specifically on the organic compounds that incorporate carbonyl groups: aldehydes and ketones. Key Terms Aldehyde Formyl group Ketone Hydrogen bonding Hydration Hydrate Objectives Identify IUPAC names for simple aldehydes and ketones Describe the boiling point and solubility characteristics of aldehydes and ketones relative to those of alkanes and alcohols Characterize the process of nucleophilic addition to the carbonyl group The carbonyl group is shown below in the context of synthesizing alcohols. This functional group is the key component of aldehydes and ketones, which we will discuss here. Nomenclature for Aldehydes and Ketones Aldehydes and ketones are structurally similar; the only difference is that for an aldehyde, the carbonyl group has at most one substituent alkyl group, whereas the carbonyl group in a ketone has two. Several examples of aldehydes and ketones are depicted below. Aldehydes are named by replacing the -e ending of an alkane with -al (similarly to the use of -ol in alcohols). The base molecule is the longest carbon chain ending with the carbonyl group. Furthermore, the carbon atom in the carbonyl group is assumed to be carbon 1, so a number is not needed in the IUPAC name to identify the location of the doubly bonded oxygen atom. If the chain contains two carbonyl groups, one at each end, the correct suffix is -dial (used in the same manner as -diol for compounds with two hydroxyl groups). An example aldehyde is shown below with its IUPAC name. One- and two-carbon aldehydes have common names (one of which you will likely be familiar with) in addition to their systematic names. Both names are acceptable. Sometimes, the carbonyl group plus one proton (called a formyl group) must be treated separately for nomenclatu Continue reading >>

Introduction To The Reactions Of Enols And Enolates

Introduction To The Reactions Of Enols And Enolates

Racemization of Carbonyl Compounds If aldehydes or ketones with an α hydrogen atom are chiral because of an asymmetric α carbon, racemization occurs relatively rapidly when these are treated with an acid or base. Why is this? Aldehydes and ketones with an α hydrogen atom are in equilibrium with their corresponding enols or enolates due to keto-enol tautomerism. The α carbon in enols and enolates is sp2-hybridized. Thus, its substituents are arranged trigonal planar. As a result, the stereochemical information of the sp3-hybridized carbonyl compound's α carbon is lost. Therefore, reconversion of the enol to the carbonyl compound does not proceed stereoselectively. Thus, racemization occurs. It must be kept in mind that racemization in the α position of carbonyl compounds (and other CH-acidic compounds) is possible when an enantioselective synthesis is constructed. α-Halogenation of CH-acidic Compounds If enolizable carbonyl compounds are treated with iodine, bromine, or chlorine, halogenation of the α carbon occurs. Halogenation yields different products depending on whether the reaction conditions are acidic or basic. Acid-catalyzed α-halogenation Acid-catalyzed α-halogenation leads to the exchange of only one α hydrogen for a halogen even if the α carbon carries additional hydrogens. In the initial reaction step, the enol nucleophilically attacks the halogen molecule. As a result, the halogen molecule is heterolytically cleaved and a single bond between the α carbon and a halogen atom is formed. That is, the reaction step yields a halide anion, as well as a protonated and, thus, positively charged α-halocarbonyl compound. Deprotonation results in the formation of the α-halocarbonyl compound. Under acidic conditions, the enol is continually supplied throu Continue reading >>

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