A-cyanocarbonyl compounds

Two different carbon functional groups can be introduced simultaneously into 1,2-positions of aromatic skeletons based on a novel insertion reaction of arynes (101) into a carbonyl-cyanomethyl a-bond of a-cyanocarbonyl compounds (102) to produce 1,2-disubstituted aromatics (103).134... 

The oxaziridine 13a reacts with a variety of P-dicarbonyl and a-cyanocarbonyl compounds under base catalysis (Eq. 162).149... 

Enolates of (3-dicarbonyl and a-cyanocarbonyl compounds have a strong tendency to form diazo compounds with arenesulfonyl azides. a-Substituted substrates react normally to give azides482 483 but even then a diazo transfer (Eq. 166)484 or other transformations319 321 484 may occur as side reactions. 

The insertion of arynes into a-cyanocarbonyl compounds occurs smoothly under the same mild reaction conditions, and by a similar reaction pathway [37]. In the case of the sterically hindered substrate pivaloylacetonitrile, a single product 41 is formed in excellent yield (Equation 12.25), whereas a mixture of 42 and the double addition product 43 were usually obtained when other a-cyanocarbonyl compounds were used (Equation 12.26). 

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