Carbonyl compounds synthesis from nitriles

A useful synthesis of polysubstituted pyridines (i.e., 11) is based on the legioselective addition of Uthiated -enaminophosphonates to unsaturated carbonyl compounds. These pyridines can also be obtained via a one-pot reaction from metalated phosphonates and sequential addition of nitriles and unsaturated caibonyl compounds <96TL(37)4577>. 

This methodology is also an important and potentially valuable method for C—N bond formation using the amination of carbon nucleophiles with electrophilic nitrogen transfer reagents (Scheme 1) Amination of ordinary carbanions and a-carbanion derived from carbonyl compounds and nitriles provides an important method for the synthesis of amines and a-amino carbonyl compounds and nitriles", respectively. For this purpose, a number of electrophilic amination reagents, which are synthetic equivalents of the R2N+ synthon, have been developed and the synthetic potential of electrophilic amination of carbon nucleophiles has been studied in detail . ... 

Recently, Verkade and coworkers have reported the successful synthesis of /3-hydroxy-nitriles from carbonyl compounds in a reaction promoted by strong nonionic bases, such as proazaphosphatrane types. The reaction occurs in the presence of magnesium sulfate. 

The synthesis of a,p-unsaturated carbonyl compounds and nitriles by Pd-catalyzed reaction [245] of allyl p-oxo esters and allyl a-cyano esters is an oxidative process. With the contra-polarizability of the metal ion, elimination of a hydride from the p-position is electronically favorable. 

Many other uses of a-sulfinyl carbanions are found in the literature, and in the recent past the trend has been to take advantage of the chirality of the sulfoxide group in asymmetric synthesis. Various ways of preparation of enantiopure sulfoxides have been devised (see Section 2.6.2) the carbanions derived from these compounds were added to carbonyl compounds, nitriles, imines or Michael acceptors to yield, ultimately, with high e.e. values, optically active alcohols, amines, ethers, epoxides, lactones, after elimination at an appropriate stage of the sulfoxide group. Such an elimination could be achieved by pyrolysis, Raney nickel or nickel boride desulfurization, reduction, or displacement of the C-S bond, as in the lactone synthesis reported by Casey [388]. 

Synthesis of Af-acylenamines from carbonyl compounds and nitriles... 

In this case the carboxonium ion captures an external nucleophile which gains electrophilic properties due to this addition. The reaction of carbonyl compounds with nitriles stimulating by acylium ions142 (equation 103) as well as the known synthesis of chalcones 363 from aldehydes and acetylenes154 (equation 104) belong to this type of rearrangement. 

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