66741-06-8Relevant academic research and scientific papers
Direct Access to α,β-Unsaturated Ketones via Rh/MgCl2-Mediated Acylation of Vinylsilanes
Chen, Zi-Yan,Deng, Xue-Zu,Song, Yang,Xue, Fei,Yamane, Motoki,Yue, Yan-Ni
, p. 12693 - 12704 (2021/09/28)
We report herein the facile and practical construction of α,β-unsaturated ketones via rhodium-catalyzed direct acylation of vinylsilanes with readily available and abundant carboxylic acids. This protocol features access to a diverse array of synthetically useful functionalities with moderate to excellent yields. More importantly, the late-stage functionalization of pharmaceuticals was also realized with synthetically useful yield.
Enantioselective Hydroazidation of Trisubstituted Non-Activated Alkenes
Meyer, Daniel,Renaud, Philippe
supporting information, p. 10858 - 10861 (2017/08/30)
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 were thus obtained in yields of 59–81 % and enantioselectivities of up to 94:6 e.r. (98:2 e.r. if the intermediate dialkylborane is purified by crystallization). A rapid access to enantiomerically pure (+)-rodocaine is also described. The use of other arenesulfonyl radical traps enables enantioselective hydroallylation, hydrosulfanylation, and hydrobromination reactions with yields of 71–86 %.
Silanes in Organic Synthesis. 8. Preparation of Vinylsilanes from Ketones and Their Regiospecific Cyclopentenone Annulation
Paquette, Leo A.,Fristad, William E.,Dime, David S.,Bailey, Thomas R.
, p. 3017 - 3028 (2007/10/02)
A general method is described for the formation of vinylsilanes from ketones.Thus, conversion to the benzene- or p-toluenesulfonylhydrazone and sequential treatment with n-butyllithium and chlorotrimethylsilane in anhydrous tetramethylethylenediamine proceeds regiospecifically to afford the less substituted vinylsilane (in unsymmetrical cases).Friedel-Crafts acylation with acryloyl chlorides and aluminium chloride and subsequent Nazarov cyclization with Lewis acid catalysis results in cyclopentenone annulation.Numerous examples that reveal the scope of this processare described.Due to accompanying polymerization, annulation with acryloyl chloride itself is least efficient.This complication can, however, be averted through use of β-chloropropionyl chloride and dehydrochlorination with 1,5-diazabicycloundec-5-ene prior to ring closure.
