The kinetics of the hydrolysis of p-nitrophenyl esters of three types of single-chain carbo- xylic acids, namely, saturated, olefinic and acetylenic, was investigated in two aquiorgano binary sol- vent systems, DMSO-H...The kinetics of the hydrolysis of p-nitrophenyl esters of three types of single-chain carbo- xylic acids, namely, saturated, olefinic and acetylenic, was investigated in two aquiorgano binary sol- vent systems, DMSO-H_2O and dioxane (DX)-H_2O. The ester probes used are: octanoie (C8), do- decanoic (C12), stearic (C18), oleic (C18-ol), elaidic (C18-el) and stearolic (C18-st). The order of measured CAgC values is: C18-ol>C18-el>C18>C18-st, whereas the order of decreasing magnitude of the observed hydrolytic rate constants of the monomeric species (km) is: C18 >C18-el>C18-ol> C18-st. These rather unanticipated results are discussed.展开更多
This paper reports the reactions of a monomeric aluminum dihydride LAlH2(L = HC[C(Me)N(Ar)]2,Ar = 2,6-i-Pr2C6H3) with diazo,azido,and terminal alkyne compounds.The reaction of LAlH2 with N2CH(SiMe3) and N3(1-Ad) occur...This paper reports the reactions of a monomeric aluminum dihydride LAlH2(L = HC[C(Me)N(Ar)]2,Ar = 2,6-i-Pr2C6H3) with diazo,azido,and terminal alkyne compounds.The reaction of LAlH2 with N2CH(SiMe3) and N3(1-Ad) occurred through an Al-H addition to end-on nitrogen to yield respective compounds LAl[N(H)N = CH(SiMe3)]2(1) and LAl[N(H)N=N(1-Ad)]2(2),while the reaction of LAlH2 with PhC≡CH occurred through a stepwise deprotonation to yield LAlH(C≡CPh)(5) and LAl-(C≡CPh)2(6),respectively.2 further reacted by N2-release to yield LAl[NH(1-Ad)][N(H)N=N(1-Ad)](3) and LAl[NH-(1-Ad)]2(4) upon the increased temperature treatment.Compounds 1-6 have been fully characterized,revealing novel reactivity patterns of LAlH2 toward different substrates under the steric influence from the bulky L ligand at Al.展开更多
基金Project supported by the National Natural Science Foundation of China.
文摘The kinetics of the hydrolysis of p-nitrophenyl esters of three types of single-chain carbo- xylic acids, namely, saturated, olefinic and acetylenic, was investigated in two aquiorgano binary sol- vent systems, DMSO-H_2O and dioxane (DX)-H_2O. The ester probes used are: octanoie (C8), do- decanoic (C12), stearic (C18), oleic (C18-ol), elaidic (C18-el) and stearolic (C18-st). The order of measured CAgC values is: C18-ol>C18-el>C18>C18-st, whereas the order of decreasing magnitude of the observed hydrolytic rate constants of the monomeric species (km) is: C18 >C18-el>C18-ol> C18-st. These rather unanticipated results are discussed.
基金supported by the National Natural Science Foundation of China (20842006, 20972129, and 20902112)China Postdoctoral Science Foundation (20090460748)+1 种基金the Fund for New Teacher of Higher Education (200803841012)the Project Sponsored by SRF for ROCS, SEM (2009060011500466)
文摘This paper reports the reactions of a monomeric aluminum dihydride LAlH2(L = HC[C(Me)N(Ar)]2,Ar = 2,6-i-Pr2C6H3) with diazo,azido,and terminal alkyne compounds.The reaction of LAlH2 with N2CH(SiMe3) and N3(1-Ad) occurred through an Al-H addition to end-on nitrogen to yield respective compounds LAl[N(H)N = CH(SiMe3)]2(1) and LAl[N(H)N=N(1-Ad)]2(2),while the reaction of LAlH2 with PhC≡CH occurred through a stepwise deprotonation to yield LAlH(C≡CPh)(5) and LAl-(C≡CPh)2(6),respectively.2 further reacted by N2-release to yield LAl[NH(1-Ad)][N(H)N=N(1-Ad)](3) and LAl[NH-(1-Ad)]2(4) upon the increased temperature treatment.Compounds 1-6 have been fully characterized,revealing novel reactivity patterns of LAlH2 toward different substrates under the steric influence from the bulky L ligand at Al.