Catalytic reaction of methyl diazoacetate with 1-methyl-2-alkenylpyrroles

Abstract

1. The reaction of 1-methyl-2-alkenylpyrroles with methyl diazoacetate at 20–50°C in the presence of CuCl leads to the formation of both adducts of the carbene at the exocyclic double bond, namely, esters of (1-methyl-2-pyrrolyl)cyclopropanecarboxylic acids, and the products of the insertion of the carbene at the 5- and 4-C-H bonds of the pyrrole ring. 2. The competitive reactions method was used to show that the introduction of one or two methyl groups at the β-position of the vinyl group of 1-methyl-2-alkenylpyrroles reduces its relative activity by factors of 1.8 and 2.7, respectively, and increases the activity of the pyrrole ring by a factor of about 2.