Copper-Catalyzed Direct Transformation of Secondary Allylic and Benzylic Alcohols into Azides and Amides: An Efficient Utility of Azide as a Nitrogen Source
作者:Balaji V. Rokade、Karthik Gadde、Kandikere Ramaiah Prabhu
DOI:10.1002/ejoc.201500010
日期:2015.4
synthesis of amides has been explored by using secondary alcohols, Cu(ClO4)2·6H2O as a catalyst, and trimethylsilyl azide (TMSN3) as a nitrogen source in the presence of 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) at ambient temperature. This method has been successfully adapted to the preparation of azides directly from their corresponding alcohols and offers excellent chemoselectivity in the formation
The direct preparation of functionalised cyclopropanes from allylic alcohols or α-hydroxyketones using tandem oxidation processes
作者:Graeme D. McAllister、Magalie F. Oswald、Richard J. Paxton、Steven A. Raw、Richard J.K. Taylor
DOI:10.1016/j.tet.2005.12.078
日期:2006.7
carried out in the presence of a stabilised sulfurane, and the intermediate α,β-unsaturated carbonyl compound undergoes in situ cyclopropanation. By using a combination of stabilisedphosphorane and sulfurane, the direct conversion of allylic alcohols or α-hydroxyketones into functionalised cyclopropanes is achieved, with in situ cyclopropanation being followed by Wittig olefination, or vice versa. The
Tandem Oxidation Processes for the Preparation of Functionalized Cyclopropanes
作者:Magalie F. Oswald、Steven A. Raw、Richard J. K. Taylor
DOI:10.1021/ol0483394
日期:2004.10.1
[reaction: see text] A novelmanganese dioxide-mediated tandem oxidation process (TOP) has been developed which allows the direct conversion of allylicalcohols into cyclopropanes, the intermediate aldehydes being trapped in situ with a stabilized sulfur-ylide. This methodology has been applied successfully to a variety of allylicalcohols and to a formal synthesis of the simple, naturally occurring
Deoxygenative Allylation of Benzyl Acetates and Cinnamyl Alcohols Catalyzed by Molecular Iodine
作者:J. S. Yadav、B. V. Subba Reddy、A. Srinivas Reddy、B. Eeshwaraiah
DOI:10.1246/cl.2007.1500
日期:2007.12.5
Benzyl acetates undergo smooth deoxygenative allylation with allyltrimethylsilane in the presence of 10 mol % of molecular iodine under mild conditions to afford the corresponding allyl derivatives in excellent yields and with high selectivity. Cinnamyl alcohols also react readily with allylsilane under similar conditions. The use of molecular iodine makes this method quite simple, more convenient
One-Pot Enol Silane Formation–Allylation of Ketones Promoted by Trimethylsilyl Trifluoromethanesulfonate
作者:C. Wade Downey、Elizabeth D. Heafner、Xuechun Lin、Alexa H. Connors、Hanyu Zhong、R. Joseph Coyle、Yiqi Liu
DOI:10.1055/a-1959-2505
日期:——
Ketones and related substrate classes undergo enol silane formation in the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf) and triethylamine, reaction conditions that also promote the in situ ionization of allyl propionates. When these two processes are performed in one pot, allylation of the ketone is observed in high yields. Aldehydes, esters, and thioesters also serve as enol silane