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2

The type of solvent used is generally not major factor in determining the enol content formed in an keto-enol tautomerism. Generally it is overshadowed by other factors like aromaticity and hydrogen bonding. But this being said doesn't mean that solvent has no role to play in the enol content. As you mentioned a polar medium prefers the keto form whereas a ...


6

The reduction of alkyl halides to the corrosponding alkane by $\ce{LiAlH4}$ is well known reaction: $$\ce{R-X + LiAlH4 -> R-H + AlH3 + LiX}$$ This reaction has been studied in some details (For example, Ref.1). Accordingly, the major product from the reaction of 4-chloropentanal and $\ce{LiAlH4}$ would be pentanol after simultaneous carbonyl and halide ...


7

It will depend on strict control of the equivalents of reductant, your work-up conditions and your control of temperature during the workup. The intial product of the reduction is the aluminium alkoxide. If you use a proton source such as $\ce{HCl (aq)}$ or $\ce{NH4Cl (aq)}$ to quench the alkoxide and keep the reaction mixture cold then you will get the 4-...


18

Does folic acid contain a benzyl or a phenyl group? This is the question asked in the title. At the first glance to the structure, one would say folic acid consists of phenyl function but not benzyl function because the question did not define what is the phenyl group. In reality, phenyl group $(\ce{Ph})$ is $\ce{C6H5}$. As Poutnik pointed out in the ...


5

D and L configuration of sugars: Draw the given sugar (aldose) in the Fischer projection with the most oxidized carbon at the top (i.e. aldehyde carbon). If it is a ketose, make the closest terminal carbon to the keto group at the top. Now: if the $\ce{OH}$ on the bottom chiral center points to the right hand side, the sugar is referred to as D-sugar. if ...


3

but here we are shifting the carbocation from secondary to primary Firstly the shift is not from secondary to primary but from tertiary to secondary. I was told that methyl shift is done to stabilise the carbocation Yes, a methyl shift is done to stabilise a carbocation. And it is done in this case for the same reason, to increase the relative stability. ...


2

TsOH is a relatively strong organic acid (Source: Wikipedia). It is used to protonate the carbonyl oxygen and make the carbon atom more electrophilic, thus facilitating nucleophilic addition of the amine. Benzene acts as a solvent in this case. It can dissolve the less polar cyclohexanone. Also, since benzene is a non-polar solvent, strong mineral acids (...


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Mechanism I developed from the paper @user55119 graciously provided. Appreciate it! Any refinements I appreciate. :)


1

I think here you are missing the point on what exactly a HOMO and a LUMO are. They are descriptions of the energy splitting that occurs when quantum wave functions constructively, or destructively, interfere with eachother when in proximity. Because this system is not conjugated, the alkene and the carbonyl with both INDIVIDUALLY have their own HOMO and ...


8

I see what went wrong. Such questions are often confused with aldol or cannizarro as they have a carbonyl group and a base is given. Actually this is a completely different name reaction called Favorskii rearrangement. The key to identify it is that its applicable to α-halo ketones. In Favorskii rearrangement, the base takes α-hydrogen from that side of ...


2

The following paragraph from chem.libretext.org1 sums up the answer to your question: Acid chlorides react with Grignard reagents to produce tertiary alcohols. Two equivalents of the Grignard reagent are needed because the first equivalent reacts to form a ketone which then reacts with the second equivalent. Because of the high reactivity of the Grigard ...


4

Yes, it is important to convert your silver ion to diamminesilver(I) complex. If you do not add ammonia to silver nitrate, the silver ion is reduced so quickly that colloidal silver metal would appear and the solution would become a black, cloudy liquid and you won't get the silver mirror when it reacts with aldehyde. It is also important that you maintain ...


4

Your line of thought possibly is influenced by the Walden inversion which is characteristic for the nucleophilic substitution mechanism of $\mathrm{S_N2}$ where steric hindrance affects the rate when this umbrella-like structure flips upon entry of the nuclophile and departure of the nucleofuge around a formally $\mathrm{sp^3}$ hybridized center: (credit) ...


8

Because the target structure contains the motif of a cyclohexane-1,2-diol, I suggest an approach including a Diels-Alder reaction (DA in the illustration below) of 1,3-butadiene and the commercially available diethyl acetal of propargyl aldehyde: The hydrolysis of the acetal then sets the stage to install the methyl group with the cuprate and 1,4-...


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