A direct and metal free one-pot method has been developed for the stereoselectivesynthesis of tetrahydropyrimidinone derivatives from a vinyl arene and formaldehyde using a tartaric acid–dimethylurea (TA : DMU) melt as a green reaction medium. The substrate scope of this method is very general and the tetrahydropyrimidinone (THPM) derivatives are synthesized in good yields with a high degree of diastereoselectivity
Reduction of Cyclic Group 6 Fischer Carbene Complexes: A Case of Exquisite Regioselectivity
作者:Pedro Ramírez-López、Mar Gómez-Gallego、María José Mancheño、Miguel A. Sierra、Montse Bilurbina、Susagna Ricart
DOI:10.1021/jo0267347
日期:2003.5.1
The reduction of alpha,beta-unsaturated cyclic group 6 metal-carbenecomplexes strongly depends on the electronic profile of the groups attached both to the carbene and the beta-carbon and occurs with exquisite regioselectivity. Thus, for complexes 8 the reduction does not take place at the carbenecarbon but exclusively at the gamma-carbonyl group. The resulting alkoxide 20 evolves to a tricyclic