The 1,4-addition of primary alcohols, higher nitroalkanes, and a Schiff's base of an alpha-amino ester to alpha,beta-unsaturated substrates produces the corresponding products in moderate to excellent yields when carried out at -63 to 70 degreesC in the presence of catalytic amounts of the nonionic strong bases P(RNCH2CH2)(3)N (R = Me, i-Pr, i-Bu) in isobutyronitrile. Diastereoselectivity for the anti form of the product is high in the case of the Schiff's base in the absence of lithium ion. These catalysts are easily removed from the product by either column filtration through silica gel or via aqueous workup.
A rapid and divergent access to chiral azacyclic nucleoside analogues via highly enantioselective 1,3-dipolar cycloaddition of β-nucleobase substituted acrylates
A rapid and divergent access to chiral azacyclic nucleoside analogues was developed via enantioselective 1,3-dipolar cycloaddition of β-nucleobase substituted acrylates.
Asymmetric Construction of 3-Azabicyclo[3.1.0]hexane Skeleton with Five Contiguous Stereogenic Centers by Cu-Catalyzed 1,3-Dipolar Cycloaddition of Trisubstituted Cyclopropenes
作者:Hua Deng、Wu-Lin Yang、Fei Tian、Wenjun Tang、Wei-Ping Deng
DOI:10.1021/acs.orglett.8b01686
日期:2018.7.6
A highly diastereo- and enantioselective desymmetrization of prochiral cyclopropenes via a Cu(CH3CN)4BF4/Ph-Phosferrox complex catalyzed 1,3-dipolar cycloaddition of azomethine ylides was described. A variety of complex 3-azabicyclo[3.1.0]hexane derivatives bearing five contiguous stereogeniccenters and two all-carbon quaternarystereogeniccenters were directly synthesized as a single isomer in excellent
Remote Substituent Effects on the Stereoselectivity and Organocatalytic Activity of Densely Substituted Unnatural Proline Esters in Aldol Reactions
作者:María de Gracia Retamosa、Abel de Cózar、Mirian Sánchez、José I. Miranda、José M. Sansano、Luis M. Castelló、Carmen Nájera、Ana I. Jiménez、Francisco J. Sayago、Carlos Cativiela、Fernando P. Cossío
DOI:10.1002/ejoc.201500160
日期:2015.4
Financial support was provided by the Spanish Ministerio de Economia y Competitividad (MINECO) and the Fondo Europeo de Desarrollo Regional (FEDER) (projects CTQ2010-16959/BQU, CTQ2012-35535, CTQ2013-40855-R, CTQ2007-62771/BQU, CTQ2010-20387, CTQ2010-17436, and Consolider-Ingenio CSD2007-00006), the University of the Basque Country (UPV/EHU, UFI11/22 QOSYC), the Basque Government (GV/EJ, grant IT-324-07)
财政支持由西班牙经济与竞争部 (MINECO) 和 Fondo Europeo de Desarrollo Regional (FEDER) 提供(项目 CTQ2010-16959/BQU、CTQ2012-35535、CTQ2013-40855-R、CTQ2007/BQU102 -20387、CTQ2010-17436 和 Consolider-Ingenio CSD2007-00006)、巴斯克地区大学(UPV/EHU、UFI11/22 QOSYC)、巴斯克政府(GV/EJ,授予 IT-324-07)、 Generalitat Valenciana-FEDER (PROMETEO/2009/039)、Gobierno de Aragon-FSE(研究组 E40)和阿利坎特大学。M. D. GR 感谢 Donostia 国际物理中心 (DIPC) 的博士后合同。MS 和 LC 非常感谢 MINECO
A Chiral Secondary Amine–Amidophosphane Precatalyst for Silver-Catalyzed Asymmetric 1,3-Dipolar Cycloaddition Reactions
作者:Haifei Wang、Xiaojun Zheng、Qifu Deng、Qinglin Hou、Kaiqiang Zhang、Pushan Wen、Shunqin Hu
DOI:10.1055/s-0037-1609492
日期:2018.6
efficient multifunctional precatalyst in the asymmetric 1,3-dipolarcycloaddition of azomethine ylides, including a series of heterocyclic, aliphatic, and 2-substituted azomethine ylides, and aromatic α,β-unsaturated aldehyde derived imino esters with different electron-deficient alkenes, as well as the three-component reaction of α-imino esters generated in situ by using N,N′-diisopropylcarbodiimide
Highly enantioselective 1,3-dipolar cycloaddition of azomethine ylides catalyzed by AgOAc/TF-BiphamPhos
作者:Chun-Jiang Wang、Zhi-Yong Xue、Gang Liang、Zhou Lu
DOI:10.1039/b902556a
日期:——
A novel and highly efficient AgOAc/TF-BiphamPhos catalytic system shows excellent reactivity, diastereo-/enantioselectivity and structural scope in asymmetric 1,3-dipolar cycloaddition of azomethine ylides, especially derived from various α-substituted α-amino acids, with N-substituted maleimides and other electron-deficient alkenes.