Platinum(II) cis-dimethyl and cis-dineopentyl complexes bearing the alkyl-substituted bis-NHC ligands L t-Bu , L Me , and L i-Pr (L t-Bu = 1,1′-di-tert-butyl-3,3′-methylenediimidazolin-2,2′-diylidene, L Me = 1,1′-dimethyl-3,3′-methylenediimidazolin-2,2′-diylidene, L i-Pr = 1,1′-diisopropyl-3,3′methylenediimidazolin-2,2′-diylidene) as well as novel cisalkyl chloro and cis-alkyl hydrido compounds were synthesized. The reactivity of the dimethyl complexes toward dichloromethane and methanol was investigated. Reductive elimination of alkanes from cis-alkyl hydrido complexes requires much higher temperatures than in related bisphosphine systems, which limits their applicability for the generation of reactive, bent platinum(0) d 10 -ML 2 fragments for bond-activation chemistry. The platinum(II) complexes were characterized by NMR and IR spectroscopy, mass spectrometry, elemental analysis, and X-ray diffraction in most cases.
Highly enantioenriched secondary alcohols were synthesized by treatment of a-carbamoyloxy-2-alkenylboronates and acarbamoyloxy-alkylboronates with Grignard reagents. An intermediary boronate complex was transformed stereospecifically to the corresponding secondary 2-alkenyl-and alkylboronates by migration of an introduced residue. Oxidative workup furnished the enantioenriched secondary alcohols.
IR spectra were recorded on IRPrestige-21, Shimadzu FTIR spectrophotometer. 1 HNMR spectra were obtained on a Avance Bruker-400MHz spectrometer and 13 C NMR were obtained on a Avance Bruker-75MHz spectrometer., Samples were analysed in CDCl 3 and the chemical shift
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.