described above to give 0.08 g (20%) of cts-diol 1 and 0.10 g (24%) of frons-diol 4.Preparation of Benzyl Ether 19.-A dispersion of 53% sodium hydride in mineral oil (3.24 g of sodium hydride, 0.135 mol) was washed with three 50-ml portions of dry pentane under nitrogen.After the final wash the residual pentane was evaporated in vacuo and 60 ml of dimethyl sulfoxide was added dropwise under nitrogen. The resulting solution was stirred at room temperature for 0.5 hr. To this solution was added dropwise over a period of 5 min a solution of 13.70 g (0.090 mol) of 1632 j [a]26d -26.26°( c 2, CHCls)! in 40 ml of dimethyl sulfoxide, and the mixture was stirred at room temperature for 10 hr. To this mixture was added 17.0 g (0.135 mol) of benzyl chloride with stirring over a period of 0.5 hr. The reaction mixture was stirred for 1.0 hr, diluted with 350 ml of ice water, and extracted with pentane. The combined extracts were washed with brine, dried, and concentrated to give 26.87 g of a pale yellow oil from which crystallized 0.46 g of transstilbene. The remaining material was distilled to give 14.55 g (67%) of 19: bp 115-116°( 0.25 mm); [ ]%> -21.79°(c 3.5, CHCla); ir (CC14) 3090 (C=CH), 3050 (aromatic CH), 1640 (C=C), 1380 and 1360 (yem-dimethyl), 1055 (CO), 897 (C=
were prepared by the thermal depolymerization of pure dry trioxymethylene as described by Cohen and Reid.31 Since the rate of polymerization of formaldehyde in these solvents was relatively rapid, the optimum concentrations and scan speeds required for the necessary band resolution had to be determined by trial and error.Absorption and MCD measurements were carried out simultaneously using aliquots from the same solution. The spectra were measured at room temperature in cells of 1-cm path length. Cell blanks were obtained immediately following each sample measurement by replacing the solution with the appropriate solvent. The gelatinous polymer which was deposited on the cell windows during the time required for the measurement resulted in a decrease in the signal-to-noise but did not otherwise contribute significantly to the solution special) A. D. Cohen and C. Reid, J. Chem. Phys., 24, 85 (1956). 6475 trum. Vibrational bands were more highly resolved in perfluorohexane than in hexane.The MCD spectrum of dideuterioformaldehyde in perfluorohexane was also obtained. Although the vibrational bands were not as highly resolved as those of formaldehyde, the essential features observed in the MCD spectra of the two compounds are the same.
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