The mechanism of enyne metathesis catalyzed by first and second generation Grubbs complexes has been computationally explored at the DFT level. The relative reactivity and the regioselectivity for the reaction of differently substituted alkenes and alkynes with model Ru complexes has been studied. The usually accepted dissociative mechanism for the alkene metathesis has been explored for alkyne...

D-Threonine-L-tert-leucine-derived bifunctional phosphine, Cat. 11, catalyzed highly enantioselective [3+2] annulation of maleimides with allenes has been disclosed, allowing the synthesis of optically active functionalized bicyclic cyclopentenes containing two tertiary stereogenic centers in good to high yields along with good to high enantioselectivities.

The reaction of [8,8-(PPh(3))(2)-nido-8,7-RhSB(9)H(10)] (1) with PR(3) in a 1:2 ratio affords mixtures that contain the mono-substituted bis-PR(3)-ligated rhodathiaboranes [8,8-(PPh(3))(L)-nido-8,7-RhSB(9)H(10)] [L = PMe(2)Ph (5), PMe(3) (6)] and the corresponding tris-PR(3)-ligated compounds [8,8,8-(L)(3)-nido-8,7-RhSB(9)H(10)] [L = PMe(2)Ph (7), PMe(3) (8)]. These latter species are more conv...

A variety of homonuclear and heteronuclear transition metal carbonyl clusters have been analyzed by ultraviolet laser desorption/ionization time-of-flight mass spectrometry. The spectra were recorded in negative and positive ion modes, using both linear and reflective techniques. A range of different clusters based on different nuclearities, geometries, and ligand types, which include hydrides,...

In this study, we have developed a method to create Co6Se8 superatoms in which we program the metal-ligand bonds. We exclusively form the Co6Se8 core under simple reaction conditions with a facile separation of products that contain differential substitution of the core. The combination of Co2(CO)8 and PR3 with excess Se gives the differentially and directionally substituted superatoms, Co6Se8(...

New cationic trialkylphosphines [P(CH(2)NH(2)R){CH(2)N(R)CH(2)N(R)CH(2)}](+) (R = C(6)H(5)CH(2), a; 4-FC(6)H(4)CH(2), b), as their Cl(-) (1a, 1b), SbF(6)(-) (2a, 2b), and PF(6)(-) (3a, 3b) salts, are described. The phosphine framework is conformationally locked, in the solid state, through pairs of intramolecular N-H...N hydrogen bonds which are maintained in the Ru(II) and Rh(III) complexes 4 ...

Crystals of the title compound, C(30)H(20)F(12)P(2) or R(2)PCH(2)CH(2)PR(2) (R = 4-C(6)H(4)CF(3)), were inadvertently prepared while attempting to recrystallize a crude sample of trans-Re(Cl)(N(2))(R(2)PCH(2)CH(2)PR(2))(2) from diethyl ether. The molecule lies on a center of inversion. One of the rings lies approximately in the P-C-C-P plane; the dihedral angle is 174.53°.The other ring is not ...

The mol-ecular structure of the title compound, trans-[Cu(C2H)Cl(C26H24P2)2], consists of an Ru(II) cation, located on an inversion centre, in an octa-hedral environment defined by two chelating phosphines, one acetyl-ide and one chloride ligand. The -C CH and the chlorine ligands are disordered over two equivalent positions (0.5 occupancy each). The coordination geometry is distorted octa-hedr...

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Organo alkali metal compounds such as (n)BuLi and (Me3Si)2NK act as excellent catalyst precursors for the addition of phosphine P-H bonds to carbodiimides, offering a general and atom-economical route to substituted phosphaguanidines, with excellent tolerability to aromatic C-Br and C-Cl bonds.