Pentaerythrityl Bromide and Iodide

PENTAERYTHRITYL BROMIDE AND IODIDE (sj m.-Tetrabromo- and Tetraiodo-neo-pentane) 

3 C(CH20H)4 + 4 PBra 3 C(CH2Br)4 + 4 H3PO3 C(CH2Br)4 + 4 Nal C(CH2l)4 4 NaBr Submitted by H. B. Scuukiuk, 

The temperature must be raised slowly to avoid formation of spontaneously inflammable hydrides of phosphorus whict will ignite and destroy the preparation. A similar result occur if the phosphorus tribromide is added at 170°. 

Since the extraction is slow, it is advisable to divide th material into several portions and carry out a number of simultaneous extractions. The extractor used was a modified Soxhlet arranged so that the extractor tube is heated by the vapor o the solvent (Org. Syn. 16, 69, Note 3). 

The crude product has a disagreeable odor probably due to the presence of a compound of phosphorus. The odor may be eliminated by heating at 120°, followed by several recrystallizations. 

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