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Please login or sign up for a free trial to access the full content. Variation 2: Reaction with Carbonyl Compounds and Michael Acceptors

DOI: 10.1055/sos-SD-019-00308

Suginome, M.; Ito, Y.Science of Synthesis, (200419484.

α-Isocyano-substituted carbanions generated by the abstraction of an α-hydrogen atom also react with carbonyl compounds (Scheme 54).[‌107‌] The reaction gives the corresponding β-isocyanoalkoxide 93 as the primary adduct; however, this intermediate is in equilibrium with the corresponding 2-metalated dihydrooxazole 94 through nucleophilic attack of the alkoxide on the isocyano group. On quenching with methanol, the 2-unsubstituted dihydrooxazole 96 is obtained exclusively. The β-isocyanoalkoxide intermediate can be trapped with acetic anhydride to give the β-acetoxyalkyl isocyanide 95 selectively.

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