Reaction of trans-dichloro(ethylene)pyridineplatinum(<scp>II</scp>) complexes with substituted pyridines and ethylene: mechanism of ligand exchange and attack of free base on the co-ordinated olefin. Preparation of two zwitterionic complexes containing platinum–carbon σ-bonds
Two complexes of formula trans-[Pt(CH2CH2L)CI2L](L = 4-methylpyridine or 3,5-dimethylpyridine) have been prepared by nucleophilic attack of the free amine on the co-ordinated ethylene of trans-[Pt(C2H4)Cl2L]. Such a reaction occurs only with the more basic and less hindered pyridines. The free pyridines also exhibit nucleophilic attack on the metal centre leading to a pyridine-exchange reaction. The
A simple eight‐membered dialkoxysilane (E)‐1 prepared from 2‐pentene‐1,5‐diol, showed remarkably stable planar chirality along with high reactivity toward epoxidation, Diels–Alder reaction, and cycloaddition reaction with azide.
strained olefins in trans‐cyclooctenes serve as efficient catalysts for halolactonizations, including bromolactonizations and iodolactonizations. The trans‐cyclooctene framework is essential for excellent catalytic performance, and the substituents also play important roles in determining efficiency. These results are the first demonstration of catalysis by a trans‐cyclooctene.
An efficient synthesis of (E)-4-[7]orthocyclophene (E)-1 via photochemical isomerization of (Z)-1 has been achieved. The key intermediate (Z)-1 was synthesized from commercially available 2-(hydroxymethyl)benzenepropanol (3) in five steps: (i) group-selective Mitsunobu reaction with CH2═CHCH2CH(SO2Ph)2, (ii) oxidation of alcohol, (iii) olefination, (iv) RCM, and (v) removal of sulfones in an overall
Bonding properties of trans-PtCl2(C2H4)L. (L = Cl−, nitrogen- or oxygen-bonded ligands)
作者:M.A.M. Meester、D.J. Stufkens、K. Vrieze
DOI:10.1016/s0020-1693(00)91712-2
日期:1976.1
Vibrational (infrared and Raman) and nuclearmagneticresonance (1H and 13C) spectra of the complexes tr-PtCl2(C2H4)L are discussed in terms of the trans influence of L on the ethylene group. The ν(CC) and νs(PtC2) frequencies, the 13C chemical shift and the coupling constant 1J(195Pt-13C) of ethylene all show a small dependence on L. A lowering of the CC bond order in ethylene as indicated by a