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How Are Ketones Acidic

Carbonyls: 10 Key Concepts (part 2)

Carbonyls: 10 Key Concepts (part 2)

If you’re on the typical college cycle, chances are you’re taking Org II right now. As you are by now well aware [more aware than you wish you were, I can hear some of you say] one of the main focii of Org II is on the many different facets of carbonyl chemistry. Following on the heels of the previous post, here are five further important points to keep in mind when studying the chemistry of these species. [Note – these will be included in the second carbonyl summary sheet, currently in preparation]. Without further ado… 6. Carbonyls make adjacent alkyl groups more acidic. How much more acidic? Consider ethane. For all practical purposes, ethane is inert to base: the pKa of its hydrogens is 50. But when you exchange one of the protons of ethane for a carbonyl group (say, -COOCH3) something phenomenal happens. The acidity changes by a factor of 10 ^25. That is an incredible number to wrap your head around. The difference in chemical reactivity between different species can be incredibly, mind-bogglingly vast. We are not talking about the difference in quarterbacking ability between Peyton Manning and Dan Marino here, or even the comparative basketball skill set of LeBron James and Verne Troyer. The differences in reactivity* are truly cosmic: like comparing the width of your armspan to the length of the Milky Way galaxy. What’s going on here? Simply put, the carbonyl π system provides a “sink” for the carbanion to donate electron density, setting up a sharing of negative charge between the α-carbon and the carbonyl oxygen. The key structural feature is not so much the resonance, although that is a factor – [the lower pKa of propene (42) is a good example of resonance stabilization] The reason why the carbonyl stabilizes the carbanion so much is that the Continue reading >>

Urine Tests For Diabetes: Glucose Levels And Ketones

Urine Tests For Diabetes: Glucose Levels And Ketones

The human body primarily runs on glucose. When your body is low on glucose, or if you have diabetes and don’t have enough insulin to help your cells absorb the glucose, your body starts breaking down fats for energy. Ketones (chemically known as ketone bodies) are byproducts of the breakdown of fatty acids. The breakdown of fat for fuel and the creation of ketones is a normal process for everyone. In a person without diabetes, insulin, glucagon, and other hormones prevent ketone levels in the blood from getting too high. However, people with diabetes are at risk for ketone buildup in their blood. If left untreated, people with type 1 diabetes are at risk for developing a condition called diabetic ketoacidosis (DKA). While rare, it’s possible for people with type 2 diabetes to experience DKA in certain circumstances as well. If you have diabetes, you need to be especially aware of the symptoms that having too many ketones in your body can cause. These include: If you don’t get treatment, the symptoms can progress to: a fruity breath odor stomach pain trouble breathing You should always seek immediate medical attention if your ketone levels are high. Testing your blood or urine to measure your ketone levels can all be done at home. At-home testing kits are available for both types of tests, although urine testing continues to be more common. Urine tests are available without a prescription at most drugstores, or you can buy them online. You should test your urine or blood for ketones when any of the following occurs: Your blood sugar is higher than 240 mg/dL. You feel sick or nauseated, regardless of your blood sugar reading. To perform a urine test, you urinate into a clean container and dip the test strip into the urine. For a child who isn’t potty-trained, a pa Continue reading >>

Why Are Esters And Amides Weaker Carbon Acids Than Ketones And Acid Fluorides? Contributions By Resonance And Inductive Effects

Why Are Esters And Amides Weaker Carbon Acids Than Ketones And Acid Fluorides? Contributions By Resonance And Inductive Effects

Abstract Two computational methodologies—a vinylogue extrapolation methodology and a block localized wave function (BLW) methodology—were employed to determine the contributions by resonance and inductive effects toward the gas-phase deprotonation enthalpies at the α carbons of acetone, acetamide, acetic acid, and acetyl fluoride, which were taken to be model compounds for ketones, amides, esters, and acid fluorides, respectively. Results from the vinylogue methodology suggest that resonance serves to enhance the gas-phase deprotonation enthalpy of a ketone by 34.3 kcal/mol, an amide by 26.2 kcal/mol, an ester by 30.5 kcal/mol, and an acid fluoride by 30.8 kcal/mol. Comparably, the BLW methodology suggests those numbers to be 42.3, 31.2, 36.1, and 39.7 kcal/mol, respectively. Results from the vinylogue methodology suggest that inductive effects serve to enhance the gas-phase deprotonation enthalpy of a ketone by 11.8 kcal/mol, an amide by 12.7 kcal/mol, an ester by 15.5 kcal/mol, and an acid fluoride by 26.0 kcal/mol, and in the same order, those numbers suggested by the BLW methodology are 3.0, 6.2, 8.5, and 16.3 kcal/mol. Continue reading >>

Is A Ketone An Acid Or A Base?

Is A Ketone An Acid Or A Base?

Ketones are in fact weak acids. This comes from an ability to shift the places of the double bond and one of the hydrogen atoms, resulting in an alcohol compound with a double bond between two of the carbon atoms. This is called an enol, and is less stable than the ketone - the two are in rapid equilibrium. This enol may lose a hydrogen ion to become an enolate. This happens only when a ketone is reacted with a strong base. 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 >>

Ketones: Clearing Up The Confusion

Ketones: Clearing Up The Confusion

Ketones, ketosis, ketoacidosis, DKA…these are words that you’ve probably heard at one point or another, and you might be wondering what they mean and if you need to worry about them at all, especially if you have diabetes. This week, we’ll explore the mysterious world of ketones, including if and how they may affect you. Ketones — what are they? Ketones are a type of acid that the body can form if there’s not enough carbohydrate to be burned for energy (yes, you do need carbs for fuel). Without enough carb, the body turns to another energy source: fat. Ketones are made in the liver from fat breakdown. This is called ketogenesis. People who don’t have diabetes can form ketones. This might occur if a person does extreme exercise, has an eating disorder, is fasting (not eating), or is following a low-carbohydrate diet. This is called ketosis and it’s a normal response to starvation. In a person who has diabetes, ketones form for the same reason (not enough carb for energy), but this often occurs because there isn’t enough insulin available to help move carb (in the form of glucose) from the bloodstream to the cells to be used for energy. Again, the body scrambles to find an alternate fuel source in the form of fat. You might be thinking that it’s a good thing to burn fat for fuel. However, for someone who has diabetes, ketosis can quickly become dangerous if it occurs due to a continued lack of insulin (the presence of ketones along with “normal” blood sugar levels is not necessarily a cause for concern). In the absence of insulin (which can occur if someone doesn’t take their insulin or perhaps uses an insulin pump and the pump has a malfunction, for example), fat cells continue to release fat into the circulation; the liver then continues to churn Continue reading >>

The Many Benefits Of Ketosis

The Many Benefits Of Ketosis

Along with living an alkaline lifestyle, one of the key principles of my Magic Menopause hormone reset program is eating a ketogenic-friendly diet. This diet puts your body in a fat-burning state called ketosis. My program’s Keto-Alkaline™ Diet includes ketogenic methodologies. It also incorporates the “reality of everyday life” into one’s diet. I’ll explain what I mean about this in just a moment. First, for those of you who aren’t familiar with ketosis, let me give you a short overview. A ketogenic diet is a diet which is low in (unhealthy) carbs and high in (healthy) fats and (healthy) protein. So how does a ketogenic diet work so well at supporting fat loss and other health benefits? It’s really a simple concept at the surface, a bit more complex when you look at the actual physiology. Ketosis is all about what your body uses as fuel. Eating high carbs = high blood glucose (sugar), high insulin, stored fat… and low fat burning, low metabolism and belly fat. Your body’s fuel source is glucose, not fat. Let me explain. When you eat carbs your body’s blood glucose increases and spikes your blood sugar. Your body releases more insulin as a reaction to elevated blood glucose levels. Insulin is produced to get the glucose from your body and into the cells. There it gets converted to energy. Your body burns the glucose to make its energy and then insulin tells the cells to store their energy as carbs or fat (the unhealthy and dreaded belly fat). When you eat a lot of carbs on an ongoing basis (like many Americans do, eating a lot of processed foods, sugar, alcohol, soda and such!) insulin is continually stimulated. This can lead to a health condition called insulin resistance, where the cells start to resist the insulin. When this happens, your blood 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 >>

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 >>

Ketones On Acid

Ketones On Acid

Acids are like an aphrodisiac for carbonyl compounds: it makes them more likely to react with nucleophiles. Let me explain. I said the last two days that carbonyl carbons are important electrophiles: they bear a partial positive charge. Now, I’m going to show how you can make them even more electrophilic – more reactive. This means that reactions that normally wouldn’t happen, will now happen. First, a question: How do we make electrophiles more electrophilic? Simple: we take electrons away from them! How can we take electrons away? With carbonyls, the answer might be a bit counterintuitive. We’re going to add acid to the oxygen, and this will make the carbon more electron-poor. Sounds weird, but it actually makes sense when you think about it. Think about the resonance forms of the carbonyl: its most stable resonance form has a carbon-oxygen double bond (neutral) and the less stable resonance form has a positive charge on carbon and a negative charge on oxygen. So the “resonance hybrid” has a small partial positive charge on carbon, because of that resonance form on the right. Now let’s add acid – say, H+ . The oxygen will go from “owning” a pair of electrons, to “sharing” it with the hydrogen. So it formally “loses” an electron to give a positively charged oxygen. (Watch out though: remember that “formal charge” doesn’t tell us about electron densities: electronegativity does. So even though there’s a “formal charge” of +1 on the oxygen, it’s still electron-rich compared to hydrogen and carbon) With me so far? If this isn’t clear, write me! If everything is OK, let’s keep going. Think about what this does to the resonance forms. Now, both resonance forms have a charge of +1 . This means that the right-hand resonance form ( 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 >>

Ketosis

Ketosis

There is a lot of confusion about the term ketosis among medical professionals as well as laypeople. It is important to understand when and why nutritional ketosis occurs, and why it should not be confused with the metabolic disorder we call ketoacidosis. Ketosis is a metabolic state where the liver produces small organic molecules called ketone bodies. Most cells in the body can use ketone bodies as a source of energy. When there is a limited supply of external energy sources, such as during prolonged fasting or carbohydrate restriction, ketone bodies can provide energy for most organs. In this situation, ketosis can be regarded as a reasonable, adaptive physiologic response that is essential for life, enabling us to survive periods of famine. Nutritional ketosis should not be confused with ketoacidosis, a metabolic condition where the blood becomes acidic as a result of the accumulation of ketone bodies. Ketoacidosis can have serious consequences and may need urgent medical treatment. The most common forms are diabetic ketoacidosis and alcoholic ketoacidosis. What Is Ketosis? The human body can be regarded as a biologic machine. Machines need energy to operate. Some use gasoline, others use electricity, and some use other power resources. Glucose is the primary fuel for most cells and organs in the body. To obtain energy, cells must take up glucose from the blood. Once glucose enters the cells, a series of metabolic reactions break it down into carbon dioxide and water, releasing energy in the process. The body has an ability to store excess glucose in the form of glycogen. In this way, energy can be stored for later use. Glycogen consists of long chains of glucose molecules and is primarily found in the liver and skeletal muscle. Liver glycogen stores are used to mai Continue reading >>

Oxidation Of Aldehydes And Ketones

Oxidation Of Aldehydes And Ketones

This page looks at ways of distinguishing between aldehydes and ketones using oxidising agents such as acidified potassium dichromate(VI) solution, Tollens' reagent, Fehling's solution and Benedict's solution. Background Why do aldehydes and ketones behave differently? You will remember that the difference between an aldehyde and a ketone is the presence of a hydrogen atom attached to the carbon-oxygen double bond in the aldehyde. Ketones don't have that hydrogen. The presence of that hydrogen atom makes aldehydes very easy to oxidise. Or, put another way, they are strong reducing agents. Note: If you aren't sure about oxidation and reduction, it would be a good idea to follow this link to another part of the site before you go on. Alternatively, come back to this link if you feel you need help later on in this page. Use the BACK button (or HISTORY file or GO menu if you get seriously waylaid) on your browser to return to this page. Because ketones don't have that particular hydrogen atom, they are resistant to oxidation. Only very strong oxidising agents like potassium manganate(VII) solution (potassium permanganate solution) oxidise ketones - and they do it in a destructive way, breaking carbon-carbon bonds. Provided you avoid using these powerful oxidising agents, you can easily tell the difference between an aldehyde and a ketone. Aldehydes are easily oxidised by all sorts of different oxidising agents: ketones aren't. You will find details of these reactions further down the page. What is formed when aldehydes are oxidised? It depends on whether the reaction is done under acidic or alkaline conditions. Under acidic conditions, the aldehyde is oxidised to a carboxylic acid. Under alkaline conditions, this couldn't form because it would react with the alkali. A salt Continue reading >>

Ketoacidosis Versus Ketosis

Ketoacidosis Versus Ketosis

Some medical professionals confuse ketoacidosis, an extremely abnormal form of ketosis, with the normal benign ketosis associated with ketogenic diets and fasting states in the body. They will then tell you that ketosis is dangerous. Testing Laboratory Microbiology - Air Quality - Mold Asbestos - Environmental - Lead emsl.com Ketosis is NOT Ketoacidosis The difference between the two conditions is a matter of volume and flow rate*: Benign nutritional ketosis is a controlled, insulin regulated process which results in a mild release of fatty acids and ketone body production in response to either a fast from food, or a reduction in carbohydrate intake. Ketoacidosis is driven by a lack of insulin in the body. Without insulin, blood sugar rises to high levels and stored fat streams from fat cells. This excess amount of fat metabolism results in the production of abnormal quantities of ketones. The combination of high blood sugar and high ketone levels can upset the normal acid/base balance in the blood and become dangerous. In order to reach a state of ketoacidosis, insulin levels must be so low that the regulation of blood sugar and fatty acid flow is impaired. *See this reference paper. Here's a table of the actual numbers to show the differences in magnitude: Body Condition Quantity of Ketones Being Produced After a meal: 0.1 mmol/L Overnight Fast: 0.3 mmol/L Ketogenic Diet (Nutritional ketosis): 1-8 mmol/L >20 Days Fasting: 10 mmol/L Uncontrolled Diabetes (Ketoacidosis): >20 mmol/L Here's a more detailed explanation: Fact 1: Every human body maintains the blood and cellular fluids within a very narrow range between being too acidic (low pH) and too basic (high pH). If the blood pH gets out of the normal range, either too low or too high, big problems happen. Fact 2: The Continue reading >>

22.3 Alpha Halogenation Of Aldehydes And Ketones

22.3 Alpha Halogenation Of Aldehydes And Ketones

Objectives After completing this section, you should be able to write an equation to illustrate the alpha halogenation of aldehydes and ketones. identify the product formed from the alpha halogenation of a given aldehyde or ketone. identify the carbonyl compound, the reagents, or both, needed to prepare a given α‑halogenated aldehyde or ketone. illustrate the importance of the alpha halogenation of carbonyl compounds as an intermediate step in the synthesis of α,β‑unsaturated aldehydes and ketones. write a detailed mechanism for the acid‑catalyzed halogenation of a ketone. describe the evidence provided by kinetic experiments supporting the suggestion that the acid‑catalyzed, alpha halogenation of ketones proceeds via the rate‑determining formation of an enol. Study Notes Note: α‑bromo ketones are a good starting material to generate α,β‑unsaturated ketones by dehydrobromination. A carbonyl containing compound with α hydrogens can undergo a substitution reaction with halogens. This reaction comes about because of the tendency of carbonyl compounds to form enolates in basic condition and enols in acidic condition. In these cases even weak bases, such as the hydroxide anion, is sufficient enough to cause the reaction to occur because it is not necessary for a complete conversion to the enolate. For this reaction Cl2, Br2 or I2 can be used as the halogens. General reaction Under acidic conditions the reaction occurs thought the formation of an enol which then reacts with the halogen. 1) Protonation of the carbonyl 2) Enol formation 3) SN2 attack 4) Deprotonation Kinetic studies provide some evidence for the mechanism shown above. The rate law for the alpha-halogenation of a ketone can be given by: rate = [ketone][H+] The implication is that the rate de Continue reading >>

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