An unusual transition-metal-mediated [2 + 2 + 2] cyclization of functionalized alkenes
Abstract
The metal–η3-2-methoxycarbonylpentadienyl complexes (C5R5)M(CO)2(syn-Ti3-2-COOMe-C6H5)(RH, MW; RH, Me, M Mo) undergo a novel acid-catalysed cotrimerization with a- and (3-unsaturated ketones to afford two products with diastereoisomeric six-membered rings which have been structurally characterized by X-ray diffraction.