Metalated Nitriles: Organolithium, -magnesium, and -copper Exchange of α-Halonitriles
作者:Fraser F. Fleming、Zhiyu Zhang、Wang Liu、Paul Knochel
DOI:10.1021/jo047877r
日期:2005.3.1
dimethylcuprate reagents generating reactive, metalated nitriles. The rapid halogen−metal exchange with alkyllithium and Grignard reagents allows selective exchange in the presence of reactive carbonyl electrophiles, including aldehydes, providing a high-yielding alkylation protocol. Lithiated and magnesiated nitriles react with propargyl bromide by SN2 displacement whereas organocopper nitriles react
α-卤代腈与烷基锂,有机镁和二甲基cup酸锂试剂反应生成活性的金属化腈。与烷基锂和格氏试剂的快速卤素金属交换可在存在醛的反应性羰基亲电试剂存在下进行选择性交换,从而提供了高产率的烷基化方案。锂化和氧化镁腈通过S N 2置换与炔丙基溴反应,而有机铜腈通过S N 2'置换反应,与C-金属化腈的形成相关。
Regio- and stereocontrolled functionalization of cycloheptadiene using organoiron and organoselenium chemistry
作者:Anthony J. Pearson、Sandra L. Kole、Tapan Ray
DOI:10.1021/ja00332a050
日期:1984.10
Etude des complexes cycloheptadienyl-fer carbonyles: reactivite, conformation, enlevement du metal et cyclofonctionalisation desdienes obtenus
Etude des complexes cycloheptadienyl-fer carbonyles:reactivite,conformation,enlevement du metal et cyclofonctionalisation des diene obtenus
Syntheses of L-Fucopyranose and Its Homologs with Ring Heteroatoms Other than Oxygen. Stereocontrolled Conversion of a Common D-Arabinofuranoside Intermediate.
作者:Shunya Takahashi、Hiroyoshi Kuzuhara
DOI:10.1246/cl.1992.21
日期:——
l-Fucopyranose and a couple of l-fucosidase inhibitors, 5-deoxy-5-thio-l-fucopyranose and 1,5-dideoxy-1,5-imino-l-fucitol, were prepared from a common pentose intermediate with α-d-arabino configuration. Stereoselectivities on carbon chain elongation of the key intermediate were successfully controlled by choosing the appropriate organometallic reagents.
Novel Isomerically Pure Tetrasubstituted Allylboronates: Stereocontrolled Synthesis of α-Exomethylene γ-Lactones as Aldol-Like Adducts with a Stereogenic Quaternary Carbon Center
作者:Jason W. J. Kennedy、Dennis G. Hall
DOI:10.1021/ja016391e
日期:2002.2.1
1-alkoxycarbonyl vinylcopper(I) intermediates from the conjugate addition of organocuprates onto acetylenic esters were trapped with very high cis-addition selectivity with iodomethylboronic esters in the presence of HMPA. The resulting isomerically pure 3,3-disubstituted allylboronates react with aldehydes in a highly diastereo- and enantioselective manner, providing α-exomethylene γ-lactones with a stereogenic
Reaction of lithium dialkylcuprates with S-2-pyridyl thioates in the presence of oxygen. A carboxylic ester synthesis
作者:Sunggak Kim、Jae In Lee、Bong Young Chung
DOI:10.1039/c39810001231
日期:——
Reaction of lithiumdialkylcuprates with S-2-pyridyl thioates in the presence of oxygen affords carboxylic esters in high yields, whereas under nitrogen it affords ketones.