Radical Addition Reactions to Allylstannanes Having Substituents at C-1. Highly Efficient Synthesis of Enantiomerically Pure .alpha.-Alkylcyclopentenones, the Key Component for Synthesis of Prostaglandins by the Two-Component Coupling Process
摘要:
A highly efficient and practical method for the synthesis of enantiomerically pure 4-alkoxy-2-alkyl-2-cyclopenten-1-ones 1, the key component for the preparation of prostaglandins via the two-component coupling process, has been developed. The method involves the preparation of 4-alkoxy-2-methylene-3-(tributylstannyl) cyclopentan-1-one 6 from readily available 4-alkoxy-2-[(diethylamino)methyl]-2-cyclopenten-1-one 5 and its reaction with alkyl radicals.