Regioselective joining of prenyl units. A simple strategy for geometry control in Pd catalyzed allylic alkylations
摘要:
Either E,E-3,9-dimethylundecadien-1,11-diol or its E,Z-isomer is selectively available via Pd catalyzed allylic alkylation as a function of alkylating agent and catalyst - an observation that establishes that reactions of vinyl epoxides and their related vinyl carbonates do not proceed through a common intermediate.
A palladium‐catalyzed highly stereoselective sulfonylation of vinylethylene carbonates for the precise synthesis of structurally diverse (Z)‐allylic sulfones was achieved with excellent regioselectivity and stereoselectivity (Z/E ratio, up to 99 : 1). This protocol used inexpensive sodium sulfinates as sulfonyl sources to construct valuable (Z)‐allylic sulfones in good to excellent yields. The controlling
Carbondioxide readily reacts with 1,3-butadiene monoxide in the presence of a catalytic amount of tetrakis(triphenylphosphine)palladium under ordinary pressure at 0 °C to afford vinylethylene carbonate in a quantitative yield.
Palladium-Catalyzed Regio- and Stereoselective Cross-Coupling of Vinylethylene Carbonates with Ketimine Esters to Generate (<i>Z</i>)-Tri- and Tetra-substituted Allylic Amino Acid Derivatives
Herein we report the palladium-catalyzed regio- and stereoselective cross-coupling of vinylethylene carbonates with ketimine esters to construct allylic amino acid scaffolds. This operationally simple protocol furnished (Z)-tri- and tetra-substituted allylic amino acid derivatives in good to excellent yields with distinguished geometriccontrol under mild reaction conditions and proved to be sufficient
An efficient, one-pot protocol for the synthesis of highly functionalized cyclopentenols has been accomplished starting from vinylethylene carbonates and bissulfonylmethanes. This protocol proceeds via sequential palladium-catalyzed decarboxylative allylation and oxidative cyclization in an operationally simple manner. A wide range of substrates is well-accommodated to afford diverse cyclopentenols
从乙烯基碳酸乙烯酯和双磺酰甲烷开始,已经完成了一种用于合成高度官能化的环戊烯醇的有效的一锅法。该协议通过顺序钯催化脱羧烯丙基化和氧化环化以操作简单的方式进行。广泛的底物可以很好地适应各种环戊烯醇,以中等至良好的产率和优异的选择性。进一步的对照实验表明,可分离的 ( Z )-烯丙醇(高达Z / E = >19:1)的选择性形成是后续级联氧化环化成功的基础。
POLYMÈRES DE [4-(MÉTHYLÉTHER)-1,3-DIOXOLANE-2-ONE DE POLYÉTHER POLYOL]