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Hine and co-workers4 and applied to neopentyl alcohol by Skell, Starer and Krapcho.6 From this reaction was isolated a mixture of 2-methyl-lbutene-3-d (11, 31% yield), 2-methyl-2-butene-3-d (111, 14% yield), 2-methyl-2-butanol-3-d (IV, 3% yield) and unreacted neopentyl alcohol-1-d (2.2 g., 24% recovery), acid phthalate [a]% -1.10 (C = 9, acetone). The rotation of the rear-D H ~ ~~

stat and nitrogen bubbled through the apparatus at a rate of 50-200 ml/min. Control experiments established that the observed reaction rate is independent of flow rate. After 30 min of thermal equilibration the vessel (G) was filled with indicator solution, the buret attached and the second reactant introduced at (D). After a short induction period, trimethylamine was steadily evolved and its rate of evolution followed with the acid titrant and a timer. It was found to be most convenient to "lead" the reaction by introducing small increments of acid to (G) and noting the time of indicator change due to reaction with amine. Data obtained resembled those shown in Figure 2, and the initial reaction rate was used to evaluate the second-order rate constant by means of the equation dProduct Isolation. Essentially the same procedure was employed with Me3N+-BEIr and Et3N+-BHr substrates, using the flow method for the former material and the static method (colori-metric) for the latter. Reaction mixtures (50 ml) were prepared which contained equal molar quantities of amine-borane and (n-Bu)3P (0.20 M) in o-dichlorobenzene, thermostated at 49.6°. The reaction was then carried out as described above and allowed to proceed to essential completion. Removal of solvent (and liberated Et3N) was accomplished by pumping on a vacuum line, and the residue was examined by infrared spectroscopy. In all cases the observed infrared spectrum was essentially that of pure («-Bu)3P+-BHr as prepared by the method of Baldwin and Washburn.4Acknowledgment. This research was generously supported by National Science Foundation Grants No. GP7735 and GP4922, for which the authors express their appreciation.