The rhodium-catalyzedasymmetrichydrogenation of various β-dehydroamino acid derivatives to give optically active β-amino acids has been examined. Chiral monodentate 4,5-dihydro-3H-dinaphthophosphepines, which are easily tuned and accessible in a multi-10-g scale, have been used as ligands. The enantioselectivity is largely dependent on the nature of the substituent at the phosphorous atom and on
An easy synthesis of aryl phosphonates by oxidation from aryldichlorophosphines with iodine in good yields is described. Aryldichlorophosphines are obtained by reaction of phosphorous trichloride with some aromatics in presence of various Lewis acids. BiCl3 and Bi(OTf)3 are used for the first time and bismuth trichloride is, for the first time in the case of anisole or thioanisole phosphonylation,
Rational Design and Assembly of M<sub>2</sub>M‘<sub>3</sub>L<sub>6</sub> Supramolecular Clusters with <i>C</i><sub>3</sub><i><sub>h</sub></i> Symmetry by Exploiting Incommensurate Symmetry Numbers
作者:Xiankai Sun、Darren W. Johnson、Dana L. Caulder、Kenneth N. Raymond、Edward H. Wong
DOI:10.1021/ja0029376
日期:2001.3.1
the respective clusters while NEt(3)H(+) and NMe(4)(+) yield none of the desired products. Extension of the aufbau assembly to produce related [M(2)Pd(3)Cl(6)L(6)](4)(-), [M(2)Pd(3)I(6)L(6)](4)(-), and [M(2)Cr(3)(CO)(12)L(6)](4)(-) (M = Ti, Sn) clusters has also been realized. In addition to this aufbau approach, self-assembly of several of these [M(2)Pd(3)Br(6)L(6)](4)(-) clusters from all eleven