We report herein a visiblelight-induced oxidation of triarylphosphines under aerobic condition with excellent functional group tolerance. In this transformation, the photo catalyst 4-phenylthioxanthone acted as a photosensitizer for the in situ generation of singlet oxygen. This new approach provided a cheaper and greener method for the preparation of phosphine oxide, showing great advantages in environmental
Effect of trimethylsilyl substitution on the chemical properties of triarylphosphines and their corresponding metal-complexes: solubilising effect in supercritical carbon dioxide
for the known triphenylphosphine complexes. Again, the contrast of the (31)P NMR and (13)C NMR chemical shifts or C-O or M-Cl stretchingfrequencies, when applied, does not show an important electronic effect on the metal complex of the trimethylsilyl substituted phosphines with respect to P(C(6)H(5))(3) derivatives. Solubility measurements of complexes 3a and 3b in scCO(2) were performed. We conclude
Spectroscopic and Computational Assessment of Silicon’s Electrophilicity in Phosphinosilylium Cations
作者:Kathleen M. Riley、Andreas L. Wierschen、Stephen J. Lee、Michel R. Gagné
DOI:10.1021/acs.organomet.0c00197
日期:2020.5.26
electrophilicity of silicon in phosphinosilylium cations is reported and compared to Djukic’s DFT method of computing relative intrinsic silylicity, Π. We also establish linearcorrelations between silicon electrophilicity and 29Si NMR chemical shifts, DFT-computed silylicities, and the Tolman electronic parameter of the phosphine. These correlations were not universal, as deviations were observed for
报道了一种测定膦基硅烷基阳离子中硅亲电性的实验方法,并将其与Djukic的DFT方法(用于计算相对固有硅基性Π)进行了比较。我们还建立了硅亲电性与29 Si NMR化学位移,DFT计算的硅基和膦的Tolman电子参数之间的线性相关性。这些相关性不是普遍的,因为观察到最受位阻的膦存在偏差。膦基硅烷与添加的膦之间的分子间甲硅烷基转移实验提供了对硅亲电特性的热力学评估。这证实了相对固有的硅酸度(Π)和29Si NMR化学位移是用于半定量确定Lewis对中甲硅烷基的亲电子性的有用参数。
Synthesis and oxidation of chiral rhenium phosphine methyl complexes of the formula (η5-C5Me5)Re(NO)(PR3)(CH3): in search of radical cations with enhanced kinetic stabilities
作者:Wayne E Meyer、Angelo J Amoroso、Monika Jaeger、Jean Le Bras、Wing-Tak Wong、J.A Gladysz
DOI:10.1016/s0022-328x(00)00528-3
日期:2000.12
Reactions of racemic [(η5-C5Me5)Re(NO)(NCCH3)(CO)]+ BF4− and phosphinesPR3 (R=C6H5a; 4-C6H4CH3b; 4-C6H4-t-C4H9c; 4-C6H4C6H5d; 4-C6H4OCH3e; c-C6H11f) give the phosphinecarbonylcomplexes [(η5-C5Me5)Re(NO)(PR3)(CO)]+ BF4− (5a–5f+ BF4−; 55–95%). These are treated with LiEt3BH and then BH3·THF to give the phosphine methyl complexes (η5-C5Me5)Re(NO)(PR3)(CH3) (2a–2f, 50–86%). Cyclic voltammetry shows
外消旋的反应[(η 5 -C 5我5)的Re(NO)(NCCH 3)(CO)] + BF 4 -和膦PR 3(R = C 6 H ^ 5一; 4-C 6 H ^ 4 CH 3 b ; 4-C 6 H ^ 4 -吨-C 4 ħ 9 ç ; 4-C 6 H ^ 4 ç 6 ħ 5 d ; 4-C 6 H ^ 4 OCH 3 é ;Ç -C 6 ħ 11 ˚F)得到膦羰基配合物[(η 5 -C 5我5)的Re(NO)(PR 3)(CO)] + BF 4 - (5A - 5F + BF 4 - ; 55- 95%)。这些都与LIET处理3 BH和BH然后3 ·THF,得到膦络合物甲基(η 5 -C 5我5)的Re(NO)(PR 3)(CH 3)(图2a - 2f中,50–86%)。循环伏安法表明,新化合物2b - 2f经过化学可逆的单电子氧化,在热力学上比2a氧化(ΔE °= 0.07、0.07、0
Selective Hydrogenation Catalyst and Methods of Making and Using Same
申请人:Cheung Tin-Tack Peter
公开号:US20100228065A1
公开(公告)日:2010-09-09
A composition comprising a supported hydrogenation catalyst comprising palladium and an organophosphorous compound, the supported hydrogenation catalyst being capable of selectively hydrogenating highly unsaturated hydrocarbons to unsaturated hydrocarbons. A method of making a selective hydrogenation catalyst comprising contacting a support with a palladium-containing compound to form a palladium supported composition, contacting the palladium supported composition with an organophosphorus compound to form a catalyst precursor, and reducing the catalyst precursor to form the catalyst. A method of selectively hydrogenating highly unsaturated hydrocarbons to an unsaturated hydrocarbon enriched composition comprising contacting a supported catalyst comprising palladium and an organophosphorous compound with a feed comprising highly unsaturated hydrocarbon under conditions suitable for hydrogenating at least a portion of the highly unsaturated hydrocarbon feed to form the unsaturated hydrocarbon enriched composition.