Cycloaddition of carbonyl compounds and alkynes to (di)silenes and (di)germenes: reactivity and mechanism

The chemistry of silenes, germenes, disilenes and digermenes has been extensively studied over the last 35 years; however, not much is known about the mechanisms of many of the fundamental reactions of this class of compounds, including cycloadditions. This review describes the current understanding of the reaction pathways for the cycloaddition of carbonyl compounds and alkynes to (di)tetrelenes. The question of whether or not the cycloaddition reactions of (di)tetrelenes follow the Woodward–Hoffman rules, established for alkenes and alkynes, is addressed.