ISSN:
0030-4921
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Methylene proton chemical shifts have been studied using multiple linear regression analysis, and additive chemical shift parameters have been determined. Using a data set of 1007 chemical shifts, involving 48 different substituents, a standard error of estimate of 0.15 ppm was found for protons spread between 2.0 and 5.9 ppm. Provision was made in the data matrix for substituent effects for directly attached groups (α) and for groups attached via one intervening saturated carbon (β-substituents). The influence of groups more remotely located was assumed to be negligible. Although the parameters were optimized for deshielded methylene proton shifts, they also serve satisfactorily for the estimation of shifts in more shielded methylene cases.
Additional Material:
3 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrc.1270221104
