BOOTH, HAROLD;READSHAW, SIMON A., TETRAHEDRON, 46,(1990) N, C. 2097-2110
作者:BOOTH, HAROLD、READSHAW, SIMON A.
DOI:——
日期:——
Experimental studies of the anomeric effect. Part IV. Conformational equilibria due to ring inversion in tetrahydropyrans substituted at position 2 by the groups ethoxy, 2'-fluoroethoxy, 2',2,'-difluoroethoxy, and 2',2',2'-trifluoroethoxy
作者:Harold Booth、Simon A Readshaw
DOI:10.1016/s0040-4020(01)89776-3
日期:1990.1
Equilibrium constants (K) for ringinversionequilibria in 2-(RO)-tetrahydropyrans (R=Et, CH2CH2,F, CH2CHF2 CH2CF3) have been determined from 13C nmr spectra recorded at 145–160K in CD2Cl2 and CFCl3/CDCl3 (85/15 by volume). Additional values of K were obtained at 250–270K from the acid-catalysed equilibration of is- and trans-2- (RO) -4-methyl tetrahydropyran (R as above). Plots of inK against T-1