Premium
Controllable Si−C Bond Activation Enables Stereocontrol in the Palladium‐Catalyzed [4+2] Annulation of Cyclopropenes with Benzosilacyclobutanes
Author(s) -
Wang XingBen,
Zheng ZhanJiang,
Xie JiaLe,
Gu XingWei,
Mu QiuChao,
Yin GuanWu,
Ye Fei,
Xu Zheng,
Xu LiWen
Publication year - 2020
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201913060
Subject(s) - annulation , bicyclic molecule , palladium , chemistry , phosphoramidite , catalysis , ligand (biochemistry) , combinatorial chemistry , stereoselectivity , ring strain , ring (chemistry) , stereochemistry , medicinal chemistry , organic chemistry , receptor , dna , biochemistry , oligonucleotide
A novel and unusual palladium‐catalyzed [4+2] annulation of cyclopropenes with benzosilacyclobutanes is reported. This reaction occurred through chemoselective Si−C(sp 2 ) bond activation in synergy with ring expansion/insertion of cyclopropenes to form new C(sp 2 )−C(sp 3 ) and Si−C(sp 3 ) bonds. An array of previously elusive bicyclic skeleton with high strain, silabicyclo[4.1.0]heptanes, were formed in good yields with excellent diastereoselectivity under mild conditions. An asymmetric version of the reaction with a chiral phosphoramidite ligand furnished a variety of chiral bicyclic silaheterocycle derivatives with good enantioselectivity (up to 95.5:4.5 er). Owing to the mild reaction conditions, the good stereoselectivity profile, and the ready availability of the functionalized precursors, this process constitutes a useful and straightforward strategy for the synthesis of densely functionalized silacycles.