Formation of glycerol carbonate from glycerol and urea catalysed by metal monoglycerolates
作者:Terence W. Turney、Antonio Patti、Will Gates、Uzma Shaheen、Sanjitha Kulasegaram
DOI:10.1039/c3gc37028c
日期:——
Polymeric monoglycerolate complexes of zinc and cobalt can act as homogeneous catalysts for the one-pot synthesis of glycerol carbonate from glycerol and urea. Effects of reaction temperature, time and glycerol to urea molar ratios on glycerol carbonate selectivity and glycerol conversion have been analysed, with yields reaching 83% at 98% glycerol conversion. The proposed mechanism involves competing catalysed and uncatalysed pathways. In the catalysed pathway, an intermediate isocyanate complex, formed from reaction of urea with the metal monoglycerolate, undergoes rearrangement to form glycerol carbonate and ammonia.
Vibrational spectra of diammine diisocyanatozinc(II) Zn(NCO)2(NH3)2 and dipyridyl diisocyanatozinc(II) Zn(NCO)2(C5H5N)2
作者:H.G.M. Edwards、D.W. Farwell、I.R. Lewis、N. Webb
DOI:10.1016/0022-2860(92)80207-x
日期:1992.8
Abstract The IR and Raman spectra of Zn(NCO) 2 (NH 3 ) 2 and Zn(NCO) 2 (C 5 H 5 N) 2 are reported. The substitution of pyridine for ammonia in Zn(NCO) 2 (NH 3 ) 2 enables the spectroscopic identification of the ν(ZnN) modes of the coordinated NCO ligands to be identified. The compounds have skeletal structures which are consistent with a C 2v molecular symmetry and there is no spectroscopic evidence