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Selective Route (selective + route)
Selected AbstractsArylethyne Bromoboration,Negishi Coupling Route to E - or Z -Aryl-Substituted Trisubstituted Alkenes of ,98% Isomeric Purity.ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2010New Horizon in the Highly Selective Synthesis of Trisubstituted Alkenes Abstract The hitherto unprecedented palladium-catalyzed cross-coupling of (Z)-,-bromo-,-arylethenylboranes can be made to proceed satisfactorily through (1) the use of highly catalytically active bis(tri- tert -butylphosphine)palladium or dichloro[N,N -bis-(2,6-diisopropylphenyl)imidazol-2-yl](m -chloropyridine)palladium and (2) conversion of the dibromoboryl group to the (pinacol)boryl group. Thus, a wide variety of carbon groups can be used to substitute bromine in ,98% stereo- and regioselectivity, while suppressing the otherwise dominant ,-debromoboration. Together with the alkylethyne-based protocols, the alkyne bromoboration,Negishi coupling tandem process has emerged as the most widely applicable and highly selective route to trisubstituted alkenes including those that are otherwise difficult to access. [source] Long-chain silanes as reducing agents part 1: a facile, efficient and selective route to amine and phosphine-stabilized active Pd-nanoparticlesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 3 2010Bhanu P. S. Chauhan Abstract Recently, metal nanoparticles have found applications in various fields, which have necessitated exploration of new avenues to obtain such materials. In this publication, a hydrosilane-based reduction and characterization of resulting palladium nanoparticles is achieved using palladium acetate as nanoparticle precursor and octadecylsilane as a reducing agent. The influence of phosphine and amine ligands in the stabilization of nanoparticles is also investigated. In addition, a brief mechanistic proposal of the reduction process is also discussed. Copyright © 2009 John Wiley & Sons, Ltd. [source] Zirconium-Catalyzed Asymmetric Carboalumination of Alkenes: ZACA,Lipase-Catalyzed Acetylation SynergyADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4-5 2007Zhihong Huang Abstract ZACA,lipase-catalyzed acetylation tandem reactions provide highly efficient and selective routes to either (R)- or (S)-2-methyl-1-alkanols, making, for the first time, the ZACA-based asymmetric synthesis of 2-methyl-1-alkanols widely applicable and satisfactory. [source] Preparation of enantiomerically enriched ,-aminoorganostannanes and their applications in stereoselective synthesis,CHIRALITY, Issue 10 2010Vincent Coeffard Abstract This review deals with the preparation of chiral, nonracemic ,-aminoorganostannanes and their applications in asymmetric synthesis. The pioneering works in this field date back almost 20 years ago and since then extensive research has been carried out to develop efficient and selective routes to highly enantioenriched ,-aminoorganostannanes. The facile Sn/Li transmetalation of these compounds by n -BuLi has led to various applications in stereoselective synthesis. Selected examples using chiral ,-aminoorganostannanes as starting materials will be reported. Chirality, 2010. © 2010 Wiley-Liss, Inc. [source] | ||||||||||