Efficient Suzuki and Stille Reactions for Regioselective Strategies of Incorporation of the 1,3-Oxazole Heterocycle: Mild Desulfonylation for the Synthesis of C-4 and C-5 Monosubstituted Oxazoles

Abstract

Suzuki and Stille cross-coupling reactions are surveyed for site-selective C-4 and C-5 elaboration of 2-(phenylsulfonyl)-1,3-oxazole derivatives. Conditions for mild reductive desulfonylations provide for direct incorporation of the intact oxazole heterocycle through bonding at C-4 and C-5.

Key words

cross-coupling reactions - arylation - alkenylation - reductive desulfonylation

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