ISSN:
0192-8651
Schlagwort(e):
anomeric effects
;
boat conformers, dihydrodioxins
;
3,4-dihydro-1,2-dithiin
;
3,6-dihydro-1,2-dithiin
;
4H-1,3-dithiin
;
2,3-dihydro-1,4-dithiin
;
dihydrodithiins
;
half-chair conformers
;
hyperconjugative orbital interactions
;
relative energies
;
stereoelectronic effects
;
Chemistry
;
Theoretical, Physical and Computational Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Informatik
Notizen:
Optimized geometries and energies for 3,4-dihydro-1,2-dithiin (1), 3,6-dihydro-1,2-dithiin (2), 4H-1,3-dithiin (3), and 2,3-dihydro-1,4-dithiin (4) were calculated using ab initio 6-31G* and MP2/6-31G*//6-31G* methods. At the MP2/6-31G*//6-31G* level, the half-chair conformer of 4 is more stable than those of 1, 2, and 3 by 2.5, 3.5, and 3.6 kcal/mol, respectively. The half-chair conformers of 1, 2, 3, and 4 are 2.9, 7.1, 2.0, and 5.6 kcal/mol, respectively, more stable than their boat conformers. The calculated half-chair structures of 1-4 are compared with the calculated chair conformer of cyclohexane and the half-chair structures for cyclohexene, 3,4-dihydro-1,2-dioxin (5), 3,6-dihydro-1,2-dioxin (6), 4H-1,3-dioxin (7), and 2,3-dihydro-1,4-dioxin (8). © 1998 John Wiley & Sons, Inc. J Comput Chem 19: 1064-1071, 1998
Zusätzliches Material:
10 Ill.
Materialart:
Digitale Medien
Permalink
