Alkyl trichloromethyl ketones

Enantioselective synthesis of a-amino acids A practical and general route to a-amino acids involves enantioselective reduction of alkyl trichloromethyl ketones with catecholborane (CB) in the presence of the oxazaborolidine (S)-l (0.1 equiv.) to give (R)-alcohols 2. The (R)-alcohols (2) are converted on treatment with NaOH... 

These stability effects are apparent in the equilibrium constants for hydration of ketones and aldehydes. Ketones have values of Keq of about 10-4 to 10-2. For most aldehydes, the equilibrium constant for hydration is close to 1. Formaldehyde, with no alkyl groups bonded to the carbonyl carbon, has a hydration equilibrium constant of about 40. Strongly electron-withdrawing substituents on the alkyl group of a ketone or aldehyde also destabilize the carbonyl group and favor the hydrate. Chloral (trichloroacetaldehyde) has an electron-withdrawing trichloromethyl group that favors the hydrate. Chloral forms a stable, crystalline hydrate that became famous in the movies as knockout drops or a Mickey Finn. 

Carbon tetrachloride undergoes stepwise reduction at mercury in DMF containing TEABr [45]. Several groups of workers [46-52] have electrogenerated the shortlived trichloromethyl anion, which can react with acrylonitrile, ethyl acrylate, diethyl fumarate, alkyl monohalides, and a variety of aldehydes and ketones. De Angelis and coworkers [53] have used dichlorocarbene, generated via reduction of carbon tetra-... 

Aldehydes and ketones react with diazomethane with evolution of nitrogen. Diazonium betaines are assumed to be intermediates, and in them electron-attracting groups R such as trichloromethyl or / -nitrophenyl favor intramolecular substitution which affords epoxides in other cases, however, the removal of nitrogen is coupled with 1,2-shifts of hydrogen or alkyl or aryl groups ... 

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