ISSN:
0030-4921
Schlagwort(e):
Chemistry
;
Analytical Chemistry and Spectroscopy
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
Proton magnetic resonance spectra of two series of aminoboranes, Me2N BRPh (R = Cl, Me, Et, i-Pr, i-Bu, t-Bu and C≡CMe) and PhRN BMe2 (R = Me, Et and i-Pr), have been examined in various solvents to show that the potential barrier to internal rotation about their B—N bond is lowered in some electron-pair donor solvents. The barrier in an aminoborane decreases with increasing electron-donating power of the solvent. The barrier in alkylaminoboranes in an electronpair donor solvent was found to increase with increasing size of the substituent alkyl group, owing to the steric repulsion between the alkyl and the solvent molecule. The solvent effects of benzene resulted in downfield shifts of the proton signals due to B-substituents and in upfield shifts of the signals due to N-substituents, as expected. The formation of a 1:1 adduct of Me2N BPh(t-Bu) with carbon disulphide was found.
Zusätzliches Material:
1 Tab.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/mrc.1270030519
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