Lithium borohydride → Phenanthro[1,2-b]furan-2-methanol

To a RB flask equipped with magentic stirring bar, reflux condenser, N2 inlet tube with bubbler was added ethyl phenanthro(1,2-b]furan-2-carboxylate (H. G. Pars Pharmaceutical Laboratories, Inc., 7.9 g, 27.2 mmol), lithium borohydride (Aldrich, 0.65 g, 30 mmol) and dry THG (400 mL). The mixture was stirred at reflux for 6 h and then poured into H2O (1 L). The reaction mixture was acidified with 1N HCl and the resulting white solid was filtered, washed with additional H2O (1500 mL) then dissolved in CH2Cl2 (500 mL), dried (Na2SO4), filtered, concentrated to 200 mL and diluted to 500 mL with hexane. The resulting material was filtered, washed with hexane (100 mL) and placed in a vacuum oven overnight. A total of 6.1 g (90.1%) of phenanthro[1,2-b]furan-2-methanol, mp 125°-126° was obtained (C, H).

1. customTo a RB flask equipped with magentic stirring bar
2. temperaturereflux condenser, N2 inlet tube with bubbler
3. customdry THG (400 mL)
4. temperatureat reflux for 6 h
5. additionpoured into H2O (1 L)
6. filtrationthe resulting white solid was filtered
7. washwashed with additional H2O (1500 mL)
8. dissolutionthen dissolved in CH2Cl2 (500 mL)
9. dry with materialdried (Na2SO4)
10. filtrationfiltered
11. concentrationconcentrated to 200 mL
12. additiondiluted to 500 mL with hexane
13. filtrationThe resulting material was filtered
14. washwashed with hexane (100 mL)
15. customplaced in a vacuum oven overnight

ORD record

ord-efa05edd0d9e40019be3e1ac202fbfbf

Source dataset

uspto-grants-1989_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04855453