Palladium-mediated reductive coupling, a stereoselective approach to the 8-dehydropumiliotoxin skeleton
作者:Stephanie A. Feutran、Helena McAlonan、Paul J. Stevenson、Andrew D. Walker
DOI:10.1016/j.tetlet.2009.03.122
日期:2009.7
Reductive cyclisation of an E-vinyl bromide with an allylic acetate proceeds under palladium catalysis to give the 8-dehydropumiliotoxin skeleton, a potential advanced precursor to 8-deoxypumiliotoxin alkaloids. Control of the stereochemistry of the E-vinyl bromide precursor is achieved readily using the Kogen or Bruckner bromophosphonate reagents and the reductive cyclisation proceeds with retention
Stereoselective Preparation of (<i>E</i>)-α-Bromoacrylates from Mixtures of Brominated Ando Phosphonates
作者:Reinhard Brückner、Thomas Olpp
DOI:10.1055/s-2004-831166
日期:——
We prepared 69:31-11:89 mixtures of phosphonates 6b and 7b containing two phenoxy substituents, a CO 2 Et group, and 1 or 2 bromine atoms, respectively, at the interspersed methylene group. Deprotonating 64:36 mixtures of these reagents with NaH and adding a variety of aldehydes at 0 °C provided unsaturated α-bromoesters. Yields were typically 70-99% and E-selectivities (i.e. ester and β-substituent
我们制备了 69:31-11:89 的膦酸酯 6b 和 7b 混合物,在散布的亚甲基上分别含有两个苯氧基取代基、一个 CO 2 Et 基团和 1 个或 2 个溴原子。将这些试剂与 NaH 的 64:36 混合物去质子化,并在 0 °C 下添加各种醛,得到不饱和的 α-溴酯。产率通常为 70-99%,E-选择性(即酯和 β-取代基顺式)为 80:20-98:2。类似地,我们通过氯化膦酸酯 49 进行到 E:Z = 94:6 (80%) 的不饱和 α-氯代酯 51。
Novel Strategy for the Synthesis of the Butenolide Moiety of Peridinin
作者:Thomas Olpp、Reinhard Brückner
DOI:10.1002/anie.200460259
日期:2005.2.25
Visible-Light Organophotoredox-Catalyzed Synthesis of Precursors for Horner-Type Olefinations
作者:Marco M. Nebe、Daniel Loeper、Fabian Fürmeyer、Till Opatz
DOI:10.1002/ejoc.201800213
日期:2018.6.7
synthesis of precursors for Horner‐olefinations from indoles in a single step. Numerous functional groups are tolerated in this photoinduced radical coupling under mild conditions and the subsequent reaction with aldehydes generates 2‐(indol‐2‐yl)acrylates in high yield.