0000000000406781
AUTHOR
Jorma Korvola
Multinuclear magnetic resonance study of 1,3,3-trimethylbicyclo [2.2.1]heptan-2-one (fenchone) oxime, its five monochloro derivatives and a dehydrochlorination product
Fenchone oxime, 5-exo-chlorofenchone oxime, 6-exo-chlorofenchone oxime, 7-anti-chlorofenchone oxime, 8-chlorofenchone oxime, 9-chlorofenchone oxime and a dehydrochlorination product of 10-chlorofenchone oxime were synthesized from fenchone and the corresponding chlorofenchones. The 1H, 13C and 17O NMR spectra of the oximes and the dehydrochlorination product were recorded. The NMR data were compared with the corresponding parameters obtained earlier for fenchone and monochlorofenchones in order to determine the differences between the carbonyl and oxime substituents from the NMR spectroscopic point of view, and to assign the stereochemistry of the oxime group. This stereochemistry could not…
Multinuclear NMR study of 1,3,3-trimethylbicyclo[2.2.1]heptan-2-one (fenchone) and its six monochlorinated derivatives
1H, 13C and 17O NMR spectra of fenchone and six monochlorofenchones have been recorded. The second-order 1H NMR spectra were analysed by an iterative computer program. The 1H and 13C chlorine-induced substituent chemical shifts (SCS) were calculated. The vicinal coupling constants proved to be essential in the assignment of the chemical shifts of the geminal methyls. No clear correlation was observed between the chemical shifts of the carbonyl oxygen and the carbonyl carbon. All monochlorofenchones were previously unknown compounds and were synthesized for this work.
Mono-, bi- and polynuclear complexes of diphenylmethane with Cr, Co and Ru. Synthesis and investigation by 1H, 13C and 17O NMR
Abstract Complexes of diphenylmethane (Ph 2 CH 2 ): Ph 2 CH 2 Cr(CO) 3 ( 1 ), Ph 2 CH 2 [Cr(CO) 3 ] 2 ( 2 ), Ph 2 CH 2 Co 4 (CO) 9 ( 3 ), Ph 2 CH 2 [Co 4 (CO) 9 ] 2 ( 4 ), Ph 2 CH 2 Cr(CO) 3 Co 4 (CO) 9 ( 5 ) and Ph 2 CH 2 Ru 6 C(CO) 14 ( 6 ) have been prepared and characterized by 1 H and 13 C-and 17 O-NMR spectroscopy. Strong shielding effects are caused by the metal valence electrons on the 1 H- and 13 C-NMR chemical shifts of aromatic protons and carbons in π-coordinated ring(s) diphenylmethane. Generally, the order of these shielding effects on the nuclei of the aromatic rings in 1 H-NMR was Co 4 (CO) 9 6 C(CO) 14 3 and in 13 C-NMR Co 4 (CO) 9 3 6 C(CO) 14 . In addition, aromatic solve…
Carbohydrates as Chemical Constituents of Biowaste Composts and their Humic and Fulvic Acids
The decomposition of organic matter of source-separated biowaste during composting was followed during 18 months. Compost samples were fractionated into three parts: (i) hot water soluble extract (HWE) (ii) bitumen fraction and (iii) humic substances (humic acids (HA) and fulvic acids (FA)). Original compost samples and the HA and FA fractions were hydrolyzed with sulfuric acid for hexoses and pentoses. Quantitative spectrophotometric and qualitative GC/MS analyses of monosaccharides as trimethylsilyl ethers of the corresponding alditols were carried out.During composting, the amount of HA in the organic matter of the compost increased, the amounts of HWE and bitumen decreased and the amoun…
1H,13C and17O NMR spectroscopic study of four bicyclo [3.1.1]heptenes (derivatives of α-pinene) and four bicyclo[3.1.1]heptanes (derivatives of β-pinene)
Four derivatives of 2, 6, 6-trimethylbicyclo[3.1.1]hept-2-ene (α-pinene) and four derivatives of 2-methylene-6, 6-dimethylbicyclo[3.1.1]heptane (β-pinene) were synthesized and their 1H, 13C and 17O NMR spectra were measured, analysed and assigned. The 1H NMR spectral parameters were obtained by computer-aided analyses of the very complex multi-spin, second-order spectra. Some of the 13C NMR chemical shift assignments of these compounds reported in the literature should be changed, based on these accurate 1H NMR spectral analyses and carbon-proton chemical shift correlated spectra (COSY). The new assignments are supported by the 1J(C, H) values, which show a strong dependence on the bond ang…
1H NMR and IR spectra of methyl dichloropropanoates and butanoates
Abstract Methyl dichloropropanoates and butanoates were synthesized and their 1H NMR and IR spectra were studied. Comparisons were made with the spectral characteristics of corresponding monochlorocompounds. Special attention was given to the elucidation of the characteristic spectral features associated with particular chlorine substitution patterns. The 1H NMR of erythro and threo methyl 2,3-dichlorobutanoates were analyzed using a computer program MAOCON, a modified LAOCOON 3 program. In the spectrum of the threo form the order of the chemical shifts of protons on asymmetric carbons seems to be opposite to that reported in earlier literature. Also vicinal coupling constants J23 were foun…
13C NMR, 1H NMR and IR spectra of a series of monochloroesters of aliphatic short chain carboxylic acids
Abstract 13 C chemical shifts for 14 isomeric monochloroesters of aliphatic carboxylic acids from propanoic acid to hexanoic acid have been determined. Comparisons are made with the literature values for methyl monochloro-octanoate isomers. Substituent effects for all positions are given. Characteristic IR absorption bands are presented and comparisons are made with regard to the isomeric structure. Connections are suggested between observed trends in IR absorption frequencies and some “abnormal” chlorine substituent effects on 13 C chemical shifts. 1 H NMR spectra of these compounds are considered.
Mono-, bi- and polynuclear complexes of dimethyldiphenylsilane, diphenylether and biphenyl with Cr, Co and Ru. Synthesis and 1H, 13C, 17O and 29Si NMR spectroscopic characterization
Abstract Mono- and bimetallic transition metal carbonyls of dimethyldiphenylsilane, Ph 2 Si(CH 3 ) 2 (L1), diphenylether, Ph 2 O (L2) and biphenyl, Ph 2 (L3): Ph 2 Si(CH 3 ) 2 Cr(CO) 3 ( 1 ), Ph 2 Si(CH 3 ) 2 [Cr(CO) 3 ] 2 ( 2 ), Ph 2 Si(CH 3 ) 2 Co 4 (CO) 9 ( 3 ), Ph 2 Si(CH 3 ) 2 [Co 4 (CO) 9 ] 2 ( 4 ), Ph 2 Si(CH 3 ) 2 Cr(CO) 3 Co 4 (CO) 9 ( 5 ), Ph 2 OCr(CO) 3 ( 6 ), Ph 2 OCo 4 (CO) 9 ( 7 ), Ph 2 ORu 6 C(CO) 14 ( 8 ), Ph 2 OCr(CO) 3 Co 4 (CO) 9 ( 9 ) and Ph 2 Ru 6 C(CO) 14 ( 10 ) have been prepared and characterized by means of 1 H, 13 C, 17 O and 29 Si NMR spectroscopy. The same order of the shielding effects induced by the transition metal (Co 1 H NMR chemical shifts of the η 6 -coord…