81077-02-3Relevant academic research and scientific papers
Syntheses of mixed-metal sulfide cubane-type clusters with the novel PdMo3S4 core and reactivities of the unique tetrahedral Pd site surrounded by sulfide ligands toward alkenes, CO, tBuNC, and alkynes
Murata, Takashi,Mizobe, Yasushi,Gao, Hong,Ishii, Youichi,Wakabayashi, Takanori,Nakano, Fumio,Tanase, Tomoaki,Yano, Shigenobu,Hidai, Masanobu,Echizen, Izumi,Nanikawa, Hiroshi,Motomura, Shigeyuki
, p. 3389 - 3398 (1994)
An incomplete cubane-type cluster [Mo3S4(H2O)9]Cl4 (1) reacted with Pd black in aqueous HC1 to give a mixed-metal cubane-type cluster [PdMo3S4(H2O)9Cl]Cl3 (2). Treatment of 2 with 3.3 equiv of 1,4,7-triazacyclononane (tacn) afforded a well-defined single cubane-type cluster [PdMo3S4(tacn)3Cl]Cl3 (3), while an anion metathesis of 2 by 4-toluenesulfonate (TsO) resulted in the formation of a double cubane-type cluster [Pd2Mo6S8(H2O) 18](OTs)8 (4). Detailed structures of both 3 and 4 have been determined by X-ray crystallography. Crystal data for 3·4H2O: orthorhombic, space group P212121 a = 17.549(3) A?, V = 20.032(4) A?, c = 10.256(2) A?, V = 3605 A?3, Z = 4, and R (Rw) = 0.051 (0.062) for 4014 reflections. For 4·24H2O: triclinic, space group P1, a = 15.799(4) A?, b = 18.079(6) A?, c = 11.873(1) A?, α = 108.75(2)o, β = 108.73(1)o, γ = 70.87(3)o, V = 2944 A?3, Z = 1, R (Rw) = 0.028 (0.036) for 10 089 reflections. Cluster 3 was converted into a series of single cubane-type clusters [PdMo3S4(tacn)3(L)]4+ containing alkenes, CO, and tBuNC coordinated to the tetrahedral Pd site, by the initial anion exchange forming [PdMo3S4(tacn)3C1]X3 (8a, X = ClO4; 8b, X = BF4; 8c, X = PF6) followed by treatment with these molecules. The alkene cluster [PdMo3S4(tacn)3(cis-HOCH 2CH=CHCH2OH)](ClO4)4 (5a′) and the carbonyl cluster [PdMo3S4-(tacn)3(CO)]Cl(ClO4) 3 (6a) have been fully characterized by X-ray analyses. Crystal data for 5a′·2H2O: monoclinic, space group P21/m, a = 12.314(1) A?, b = 12.732(2) A?, c = 15.736(2) A?, β= 94.01(1)o, V = 2461 A?3, Z = 2, R (Rw) = 0.068 (0.081) for 2743 reflections. For 6a·3H2O: orthorhombic, space group Pbca, a = 15.485(13) A?, b = 23.900(6) A?, c = 23.326(7) A?, V = 8633 A?3, Z = 8, and R (Rw) = 0.061 (0.069) for 7761 reflections. Interestingly, cluster 8c catalyzes the reaction of a series of alkynic acid esters R2C≡CCOOR1 with alcohols R3OH to give the trans addition products (Z)-(R3O)R2C=CHCOOR1 (R1 = Me, Et, tBu, Ph, R2 = H, R3 = Me; R1 = R3 = Me, R2 = COOMe, Me; R1 = Ph, R2 = Et, R3 = Me; R1 = Me, R2 = H, R3 = Et, PhCH2) with quite high selectivity under mild conditions with retention of the cluster core.
Organic Synthesis with Trialkylphosphine Catalysts. Conjugate Addition of Alcohols to α,β-Unsaturated Alkynic Acid Esters
Inanaga, Junji,Baba, Yoshiyasu,Hanamoto, Takeshi
, p. 241 - 244 (2007/10/02)
The conjugate addition of alcohols to α,β-unsaturated alkynic acid esters proceeds under neutral conditions in the presence of a catalytic amount of trialkylphosphine to give the corresponding β-alkoxy-α,β-unsaturated alkenic acid in good to excellent yields.
CATALYZED INSERTION REACTIONS OF SUBSTITUTED Α-DIAZOESTERS. A NEW SYNTHESIS OF CIS-ENOATES
Ikota, Nobuo,Takamura, Norio,Young, Stanley D.,Ganem, Bruce
, p. 4163 - 4166 (2007/10/02)
The decomposition of α-diazoesters is notably catalyst-dependent; with rhodium (II) carboxylates a stereoselective insertion reaction leads to the title structures in high yield.
