Stereoselective synthesis of 2, 4, 5-trisubstituted piperidines via radical cyclization
ME Ragoussi, SM Walker, A Piccanello…
文献索引：Ragoussi, Maria-Eleni; Walker, Stephen M.; Piccanello, Andrea; Kariuki, Benson M.; Horton, Peter N.; Spencer, Neil; Snaith, John S. Journal of Organic Chemistry, 2010 , vol. 75, # 21 p. 7347 - 7357
A novel approach to 2, 4, 5-trisubstituted piperidines is reported, involving the 6-exo cyclization of stabilized radicals onto α, β-unsaturated esters. Only two of the four possible diastereoisomers are observed, with diastereomeric ratios ranging from 3: 2 to 40: 1 when the radical stabilizing group is vinyl or phenyl. Cyclization of a (triethylsilyl) vinyl-stabilized radical gives the corresponding piperidine radical as a single diastereoisomer that may ...
