Alkyl Orthoformate: A Versatile Reagent in Organic Synthesis

Introduction

Alkyl orthoformates are important intermediates for organic synthesis, widely used in medicines, pesticides and flavors. Alkyl orthoformates, in general, are transparent liquids that decompose in water and are soluble in methanol and chloroform. Alkyl orthoformates in acid media generate alkoxonium, which is a powerful electrophilic agent used as one carbon building block, and two alcohol molecules, which constitutes an important protecting groups. Alkyl orthoformates have also been reported as highly selective O, S and C-alkylating agents due to their ability to furnish methyl groups by releasing methyl formate, which is a good leaving group. Thus, alkyl orthoformates are versatile chemical reagents, used to supply nucleophilic oxygen and eletrophilic carbon atoms. Recent applications of alkyl orthoformates are shown below.

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