Chlorine versus bromine: facial selectivity in the Diels–Alder reactions of 5-bromo-1,2,3,4,5-pentachlorocyclopenta-1,3-diene
作者:Lori C. Burry、David O. Miller、D. Jean Burnell
DOI:10.1039/a805355c
日期:——
Diels–Alderreactions of diene 11 with both electron-poor and electron-rich dienophiles led to approximately 90% addition to the face of 11 syn to the C-5 chlorine. Addition of 4-phenyl-1,2,4-triazoline-3,5-dione was slightly less faciallyselective. Adduct ratios were obtained by NMR methods; stereochemistry was determined by X-ray crystallography. The results support the view that facial selectivity