Premium
Carbon‐13 NMR spectra of saturated heterocycles: XI —Tetrahydropyrans (oxanes)
Author(s) -
Eliel Ernest L.,
Manoharan Muthiah,
Pietrusiewicz K. Michal,
Hargrave Karl D.
Publication year - 1983
Publication title -
organic magnetic resonance
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.483
H-Index - 72
eISSN - 1097-458X
pISSN - 0030-4921
DOI - 10.1002/omr.1270210205
Subject(s) - extant taxon , chemistry , ring (chemistry) , spectral line , nmr spectra database , chemical shift , carbon 13 nmr , carbon fibers , resonance (particle physics) , stereochemistry , organic chemistry , mathematics , physics , atomic physics , astronomy , evolutionary biology , composite number , biology , algorithm
The 13 C NMR spectra of 62 oxanes (tetrahydropyrans) with and without methyl substituents at various ring positions, some of them bearing in addition (or instead) ethyl, vinyl, ethynyl, carbomethoxy and methylol substituents at C‐2, have been recorded, and the 294 resulting chemical shifts have been correlated by multiple linear regression analysis. Axial and equatorial α‐, β‐, γ‐, δ‐, gem ‐ and vic ‐parameters for shifts caused by methyl groups at all ring positions, and similar parameters for Et,—CHCH 2 ,—CCH, CO 2 Me and CH 2 OH groups at C‐2, are reported. Standard deviations of the parameters are, in most cases, within 0.3 ppm and the agreement of calculated and experimental shifts is excellent. This is probably the largest parameter set of this type extant. 13 C NMR spectra of a number of additional substituted tetrahydropyrans, and of 3,6‐dihydro‐2 H ‐pyrans and 3,4‐dihydro‐2 H ‐pyrans, are tabulated and discussed.