Diastereoselective and Branched-Aldehyde-Selective Tandem Hydroformylation–Hemiaminal Formation: Synthesis of Functionalized Piperidines and Amino Alcohols
作者:Rachael Pittaway、José A. Fuentes、Matthew L. Clarke
DOI:10.1021/acs.orglett.7b01049
日期:2017.6.2
developed for the synthesis of chiralfunctionalizedpiperidines, with very good diastereoselectivity and branched regioselectivity using Rh/(S,S,S)-BOBPHOS catalysts. Tandem hydroformylation–hemiacetal formation also proceeds with good diastereoselectivity (88:12), with the hemiacetal product being hydrogenated with retention of stereochemistry to give a chiral intermediate used in the synthesis of the new
Enantioselective Hydroformylation of 1-Alkenes with Commercial Ph-BPE Ligand
作者:Zhiyong Yu、Meredith S. Eno、Alexandra H. Annis、James P. Morken
DOI:10.1021/acs.orglett.5b01421
日期:2015.7.2
A rhodium complex, in conjunction with commercially available Ph-BPE ligand, catalyzes the branch-selective asymmetric hydroformylation of 1-alkenes and rapidly generates alpha-chiral aldehydes. A wide range of terminal olefins Including 1-dodecene were examined, and all delivered high enantioselectivity (up to 98:2 er) as well as good branch:linear ratios (up to 15:1).
Synthesis of antimalarial G-factors endoperoxides: relevant evidence of the formation of a biradical during the autoxidation step
In the search for new antimalarial endoperoxides related to G-factors series, L[Sin, a methodology based on autoxidation of a dienol system, Unexpected cyclic ether alcohols and hydroperoxides were obtained confirming the structure of the previously postulated biradical intermediate implicated in oxygen uptake. Antimalarial activities of PMB-endoperoxides are greatly enhanced when the peroxyhemiketal function is methylated for the G3 endoperoxide. (C) 2008 Elsevier Ltd. All rights reserved.