Science of Synthesis

Gaspar, B.; Trauner, D., Science of Synthesis: Stereoselective Synthesis, (2011) 3, 386.

The introduction of a silicon directing group can control the regioselective formation of the less substituted double bond in the cyclopentenone products.[‌17‌] For example, the vinylogous acylsilanes ‌18‌ undergo an iron(III) chloride mediated cyclization to afford the cyclopentenones ‌19‌ in moderate to excellent yield, favoring the cis-fusion in the bicyclic system (‌Scheme 6‌).[‌18‌] Various saturated and unsaturated chains, in addition to heteroatoms, are well tolerated in the reaction.

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References