Methyl Radical Initiated Kharasch and Related Reactions
作者:Nicholas D. C. Tappin、Philippe Renaud
DOI:10.1002/adsc.202001000
日期:2021.1.5
chalcogen group transfer radical additions is reported. The procedure relies on the thermal decomposition of di‐tert‐butylhyponitrite (DTBHN), a safer alternative to the explosive diacetyl peroxide, to produce highly reactive methylradicals that can initiate the chain process. This mode of initiation generates byproducts that are either gaseous (N2) or volatile (acetone and methyl halide) thereby facilitating
Enantioselective Hydroazidation of Trisubstituted Non-Activated Alkenes
作者:Daniel Meyer、Philippe Renaud
DOI:10.1002/anie.201703340
日期:2017.8.28
A one-pot procedure for the enantioselective hydroazidation of non-activated trisubstituted alkenes is described. Hydroboration with monoisopinocampheylborane (IpcBH2) provides dialkylboranes that are in situ selectively converted into monoalkyl-substituted catecholboranes; these undergo radical azidation upon treatment with benzenesulfonyl azide and a radical initiator. Enantiomerically enriched azides
A General Approach to Deboronative Radical Chain Reactions with Pinacol Alkylboronic Esters
作者:Emy André‐Joyaux、Andrey Kuzovlev、Nicholas D. C. Tappin、Philippe Renaud
DOI:10.1002/anie.202004012
日期:2020.8.10
suitable substrates. We report their in situ conversion into alkylboronic catechol esters by boron‐transesterification with a substoichiometric amount of catechol methyl borate combined with an array of radical chain processes. This simple one‐pot radical‐chain deboronative method enables the conversion of pinacol boronic esters into iodides, bromides, chlorides, and thioethers. The process is also suitable
Chain Mechanism in the Photocleavage of Phenacyl and Pyridacyl Esters in the Presence of Hydrogen Donors
作者:Jaromír Literák、Anna Dostálová、Petr Klán
DOI:10.1021/jo0521551
日期:2006.1.1
magnitude of a radical chain process is dependent on the efficiency of consecutive steps that produce freeradicals capable of a subsequent ester reduction. The driving force of a possible electron transfer from the ketyl radicals to the ester has been excluded on the basis of cyclic voltametry measurements. The observed quantum yields of photoreduction were found to be diminished by formation of relatively
A Short Synthesis of (+)‐Brefeldin C through Enantioselective Radical Hydroalkynylation
作者:Lars Gnägi、Severin Vital Martz、Daniel Meyer、Robin Marc Schärer、Philippe Renaud
DOI:10.1002/chem.201903392
日期:2019.9.6
starting from 2-furanylcyclopentene is described. This approach is based on an unprecedented enantioselectiveradical hydroalkynylation process to introduce the two cyclopentane stereocenters in a single step. The use of a furan substituent allows a high trans diastereoselectivity to be achieved during the radicalprocess and it contains the four carbon atoms C1-C4 of the natural product in an oxidation state