Prepd by the action of hydrobromic acid on trimethylene glycol in the presence of sulfuric acid: Kamm, Marvel, Org. Synth. coll. vol. I, p 30 (1941); cf. Derick, Hess, J. Am. Chem. Soc. 40, 545 (1918); Norris, Mulliken, ibid. 42, 2096 (1920): Kamm, Newcomb, ibid. 43, 2229 (1921). From trimethylene glycol and PBr3: Bogert, Slocum, ibid. 46, 765 (1924).