Novel catalytic reductions of tertiary and secondaryphosphineoxides to phosphines have been developed. Using tetramethyldisiloxane (TMDS) as a mild reducing agent in the presence of copper complexes, PO bonds are selectively reduced in the presence of other reducible functional groups (FGs) such as ketones, esters, and olefins. Based on this transformation, an efficient one pot reduction/phosphination
Palladium(0)-Catalyzed Reaction of Cyclopropylidenecycloalkanes with Carbon Dioxide
作者:Kai Chen、Min Jiang、Zhen Zhang、Yin Wei、Min Shi
DOI:10.1002/ejoc.201101192
日期:2011.12
Cyclopropylidenecycloalkanes, which are highly strained methylenecyclopropane (MCPs) containing a cycloalkane moiety, react with carbondioxide smoothly to give the corresponding five-memberedlactone derivatives in moderate to good yields through a cyclopropane ring-opening process in the presence of Pd0 catalyst and PCy3 upon heating under 40 atm of CO2. The relative configuration of the major diastereomers
环亚丙基环烷烃是含有环烷烃部分的高度紧张的亚甲基环丙烷 (MCP),在 PdO 催化剂和 PCy3 存在下,通过环丙烷开环过程与二氧化碳顺利反应,以中等至良好的收率得到相应的五元内酯衍生物。在 40 个大气压的 CO2 下加热。主要非对映异构体的相对构型已经确定,并且还提出了合理的反应机制。
First isolation and characterization of 1,2-oxaphosphetanes with three phenyl groups at the phosphorus atom in typical Wittig reaction using cyclopropylidenetriphenylphosphorane
stable crystals in the typicalWittigreaction of cyclopropylidenetriphenylphosphorane with activated carbonyl compounds. X-ray analysis of the oxaphosphetane showed that the phosphorus atom is at the center of a slightly distorted trigonal bipyramidal structure. Thermal decomposition of these oxaphosphetanes was carried out to give the starting carbonyl compounds and Wittigreaction products, olefins.
Copper-Catalyzed Cross-Coupling of Alkyl and Phosphorus Radicals for C(sp<sup>3</sup>)–P Bond Formation
作者:Cheng-Kun Li、Ze-Kun Tao、Adedamola Shoberu、Wei Zhang、Jian-Ping Zou
DOI:10.1021/acs.orglett.2c02454
日期:2022.8.19
A CuI-catalyzed cross-coupling of alkyl- and phosphorus-centered radicals for C(sp3)–P bondformation is introduced. Diacyl peroxides, generated in situ from aliphatic acids and H2O2, serve as a source for alkyl radicals and also an initiator for the generation of phosphorus radicals from H–P(O) compounds.
介绍了一种 Cu I催化的以烷基和磷为中心的自由基的交叉偶联,以形成 C(sp 3 )-P 键。由脂肪酸和 H 2 O 2原位生成的二酰基过氧化物可作为烷基自由基的来源,也是从 H-P(O) 化合物生成磷自由基的引发剂。
Highly Chemoselective Metal-Free Reduction of Phosphine Oxides to Phosphines
Unprecedented chemoselective reductions of phosphine oxides to phosphines proceed smoothly in the presence of catalytic amounts of specific Bronsted acids. By utilizing inexpensive silanes, e.g., PMHS or (EtO)(2)MeSiH, other reducible functional groups such as ketones, aldehydes, olefins, nitriles, and esters are well-tolerated under optimized conditions.