Preparation of Borohydride Exchange Resin
J. Org. Chem. 59, 4687 (1994)
An aqueous solution of sodium borohydride (1 M, 1 L) was stirred with wet chloride-form anion exchange resin (Amberlite IRA-400 (20-50 mesh), 200g) for 1 h. The resulting resin was washed thoroughly with distilled water until free from excess NaBH4. The borohydride form anion exchange resin was then dried in vacuo at 60°C for 5 h. The dried resin was analyzed for borohydride content by hydrogen evolution on acidification with 2 N HCl, and the average hydride content of BER was found to be 3.3 mmol of BH4- per gram. The dried resin was stored under nitrogen in refrigerator (-4°C). The hydride content was constant over 6 weeks.
References:
Yoon, N. M; Tetrahedron Lett. 24, 5367 (1983)
Kabalka, G; Synth. Commun. 20, 293 (1990) and references cited therein.