Studies on Pd(II)-catalyzed coupling-cyclization of alpha- or beta-amino allenes with allylic halides.
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.
Ma
Shengming
S
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai 200032, P. R. China. masm@pub.sioc.ac.cn
Yu
Fei
F
Gao
Wenzhong
W