[EN] METHODS FOR PHOSPHINE OXIDE REDUCTION IN CATALYTIC WITTIG REACTIONS<br/>[FR] PROCÉDÉS POUR LA RÉDUCTION D'UN OXYDE DE PHOSPHINE DANS DES RÉACTIONS DE WITTIG CATALYTIQUES
申请人:UNIV DUBLIN CITY
公开号:WO2014140353A1
公开(公告)日:2014-09-18
A method for increasing the rate of phosphine oxide reduction, preferably during a Wittig reaction comprising use of an acid additive is provided. A room temperature catalytic Wittig reaction (CWR) the rate of reduction of the phosphine oxide is increased due to the addition of the acid additive is described. Furthermore, the extension of the CWR to semi-stabilized and non-stabilized ylides has been accomplished by utilization of a masked base and/or ylide-tuning.
Part I: The Development of the Catalytic Wittig Reaction
作者:Christopher J. O'Brien、Zachary S. Nixon、Andrew J. Holohan、Stephen R. Kunkel、Jennifer L. Tellez、Bryan J. Doonan、Emma E. Coyle、Florie Lavigne、Lauren J. Kang、Katherine C. Przeworski
DOI:10.1002/chem.201301444
日期:2013.11.4
developed the first catalytic (in phosphane) Wittigreaction (CWR). The utilization of an organosilane was pivotal for success as it allowed for the chemoselective reduction of a phosphane oxide. Protocol optimization evaluated the phosphane oxide precatalyst structure, loading, organosilane, temperature, solvent, and base. These studies demonstrated that to maintain viable catalytic performance it was
Breaking the Ring through a Room Temperature Catalytic Wittig Reaction
作者:Christopher J. O'Brien、Florie Lavigne、Emma E. Coyle、Andrew J. Holohan、Bryan J. Doonan
DOI:10.1002/chem.201300546
日期:2013.5.3
One ring no longer rules them all: Employment of 2.5–10 mol % of 4‐nitrobenzoic acid with phenylsilane led to the development of a room temperature catalytic Wittig reaction (see scheme). Moreover, these enhanced reduction conditions also facilitated the use of acyclic phosphineoxides as catalysts for the first time. A series of alkenes were produced in moderate to high yield and selectivity.
Recycling the Waste: The Development of a Catalytic Wittig Reaction
作者:Christopher J. O'Brien、Jennifer L. Tellez、Zachary S. Nixon、Lauren J. Kang、Andra L. Carter、Stephen R. Kunkel、Katherine C. Przeworski、Gregory A. Chass
DOI:10.1002/anie.200902525
日期:2009.9.1
It's all in the ring: 3‐Methyl‐1‐phenylphospholane‐1‐oxide (4–10 mol %) and an organosilane reducing agent are the key components in the first Wittigreactioncatalytic in phosphine. The protocol also functions well on larger scale: a reaction on a 30 mmol scale yielded 3.39 g of product, corresponding to a yield of 67 %.
A method was developed for the microwave-assisted one-pot synthesis of phenylpropanoids, monolignols, and coumarins. The chosen reaction conditions determine whether a cinnamic acid or coumarin derivative is produced. The optimized reaction conditions were also applied to the synthesis of osthol (13) and several other natural products.