ISSN:
1573-8353
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract A number of previously undescribed alkyl-1,3,2-dioxaborinanes were synthesized by condensation of substituted 1,3-diols with alkylboron dichlorides or dibutyl isopropylborate. It was shown by PMR spectroscopy that the 2,5-dialkyl-1,3,2-dioxaborinane molecules are conformationally homogeneous and do not contain an axial substituent in the 5 position, whereas the 2-isopropyl-5,5-dimethyl-1,3,2-dioxaborinane molecules exist in a state of rapid ring inversion, and introduction of methyl substituents in the 4, 4, and 6 positions of the 1,3,2-dioxaborinane ring leads to distortion of the ring conformation and conformational heterogeneity of the investigated sample. The observed regularities are explained from the position of intensive “oxygen-boron” electron exchange in the heteroring. It is concluded that the 2,5-dialkyl-1,3,2-dioxaborinane molecules have primarily a conformation with a semiplanar form.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00635935
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