Stereoselective access to functionalized β-γ unsaturated acids
Stereoselective synthesis of vinylstannanes bearing a carboxylic acid function was achieved from β-γ alkynoic acids via hydrostannation, stannylcupration or silastannation reactions. Regioselectivity is highly dependent on the nature of the stannylanions used and on protection of the carboxylic acid function.
Tributylstannyl 4-tributylstannylbut-3-enoate: A useful C-4 homologating agent. Application to the synthesis of aryl iodolactones
Tributylstannyl 4-tributylstannylbut-3-enoate, readily prepared by radical hydrostannation, is used for the transfer of a but-3-enoic acid synthon. Some of the potentialities of this synthon are established by the synthesis of aryl iodolactones or tetralones (one of them is a key intemediate for ABT-200 synthesis).