Acceleration Effects of Phosphine Ligands on the Rhodium-Catalyzed Dehydrogenative Silylation and Germylation of Unactivated C(sp(3))-H Bonds

作者:Murai Masahito; Takeshima Hirotaka; Morita Haruka; Kuninobu Yoichiro; Takai Kazuhiko
来源:Journal of Organic Chemistry, 2015, 80(11): 5407-5414.
DOI:10.1021/acs.joc.5b00920

摘要

The current work describes the marked rate of acceleration caused by phosphine ligands on the rhodium-catalyzed dehydrogenative silylation and germylation of unactivated C(sp(3))-H bonds. The reactivity was affected by the steric and electronic nature of the phosphine ligands. The use of the bulky and electron-rich diphosphine ligand (R)-DTBM-SEGPHOS was highly effective to yield the dehydrogenative silylation products selectively in the presence of a hydrogen acceptor. An appropriate choice of C-2-symmetric chiral diphosphine ligand enables the asymmetric dehydrogenative silylation via the enantioselective desymmetrization of the C(sp(3))-H bond. The unprecedented catalytic germylation of C(sp(3))-H bonds with dehydrogenation was also examined with the combination of the rhodium complex and a wide bite angle diphosphine ligand to provide the corresponding 2,3-dihydrobenzo[b]germoles in good yield.

  • 出版日期2015-6-5