| Abstract
| - The reaction of heteroaromatics, such as furans, thiophenes, thiazoles, and pyrroles, withalkylidenecyclopropanes proceeded smoothly in the presence of palladium catalysts, producing thecorresponding α-allylated products in good to high yields. For example, the reaction of 3-butylpentylidenecyclopropane (1a) with 2-methylfuran (2a), ethyl 2-thiophenecarboxylate (4a), 2-isobutylthiazole (6a), and 1-methylpyrrole (11b) gave the α-allylated products in 70%, 66%, 77%, and30% yield, respectively. The reaction proceeded predominantly through distal bond cleavage. Theorder of reactivity of heteroaromatics toward 1a is as follows: furan > thiophene ≈ thiazole (5-position) > thiazole (2-position) ≈ pyrrole. This methodology provides a means for introducing anallylic group to various kinds of heteroaromatics under mild conditions.
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