Studies on Pd(II)-Catalyzed Coupling−Cyclization of α- or β-Amino Allenes with Allylic Halides
摘要:
The palladium-catalyzed coupling-cyclization of alpha- or beta-amino allenes with allylic halides leading to 3-allylic 2,5-dihydropyrroles and 1,2,3,6-tetrahydropyridines, respectively, was studied. The starting materials are easily available. The skeletons of both two classes of products were established by the X-ray diffraction studies of 7i and 9b. Through the study of the reaction of 2b with 3-chloro-1-butene, 1-chloro-2-butene, and pi-allyl palladium species and the stereochemical outcome of the coupling cyclization of (S)-2m and (R)-2n, it is believed that the current transformation most likely proceeded via a Pd(II)-catalyzed pathway, although a Pd(0) pathway cannot be completely excluded.
Studies on Pd(II)-Catalyzed Coupling−Cyclization of α- or β-Amino Allenes with Allylic Halides
摘要:
The palladium-catalyzed coupling-cyclization of alpha- or beta-amino allenes with allylic halides leading to 3-allylic 2,5-dihydropyrroles and 1,2,3,6-tetrahydropyridines, respectively, was studied. The starting materials are easily available. The skeletons of both two classes of products were established by the X-ray diffraction studies of 7i and 9b. Through the study of the reaction of 2b with 3-chloro-1-butene, 1-chloro-2-butene, and pi-allyl palladium species and the stereochemical outcome of the coupling cyclization of (S)-2m and (R)-2n, it is believed that the current transformation most likely proceeded via a Pd(II)-catalyzed pathway, although a Pd(0) pathway cannot be completely excluded.
Ru-Catalyzed Cyclocarbonylation of α- and β-Allenic Sulfonamides: Synthesis of γ- and δ-Unsaturated Lactams
作者:Suk-Ku Kang、Kwang-Jin Kim、Chan-Mo Yu、Jeong-Wook Hwang、Young-Kyu Do
DOI:10.1021/ol016281c
日期:2001.9.1
[GRAPHICS]The Ru-catalyzed cyclocarbonylation of alpha- or beta -allenic sulfonamides in the presence of Ru-3(CO)(12) (1 mol %) and Et3N (1.5 equiv) under CO atmosphere (20 atm) in dioxane at 100 degreesC for 9 h gave heterocyclic gamma- and delta -unsaturated lactams in good yields.