Reaction Steps
The compound of Example 9 (340 mg) was dissolved in tetrahydrofuran. To this solution was added borane-dimethyl sulfide complex (0.18 ml of 10M solution) and the resulting solution was heated at reflux for 8 h. The mixture was cooled, methanol added to quench excess borane, and the solvents were removed in vacuo. The residue was dissolved in methanol (10 ml) and potassium carbonate was added (238 mg). This mixture was heated at reflux for 1 hour; the methanol was removed in vacuo and the residue was dispersed between ethyl acetate and brine. The ethyl acetate layer was dried (MgSO4) and evaporated. The residue was purified by chromatography on silica using 10% ethyl acetate in petrol. The product was recrystallised from ether-hexane: mp 103°-104° C. 1H NMR d 1.4-1.5 (2H, m, CH2CH2), 1.8-1.9 (1H, m, CHHCH2N), 2.1-2.2 (2H, m, CHHCH2N and CHHN), 2.95-3.0 (1H, m, CHHN), 3.11-3.15 (1H, d, J=15.0 Hz, NCHH-furan), 3.38 (1H, s, NCHCHO), 3.54-3.58 (1H, d, J=15.0 Hz, NCHH-furan), 3.56 (1H, s, NCHCHO), 4.02-4.06 (1H, d, J=13.0 Hz, OCH H--), 4.59-4.62 (1H, d, J=13.0 Hz, OCHH--), 6.08-6.09 (1H, m, furan H), 6.35-6.36 (1H, m, furan-H), 7.24-7.32 (3H, m, ArH), 7.46-7.48 (2H, m, ArH), 7.55 (1H, s, furan-H), 7.68 (2H, s, ArH), 7.93 (1H, s, ArH); MS (CI+) m/z 485 (M+ +1, 100%). Found: C, 62.11; H, 4.80; N, 2.90. Calcd. for C25H23NF6O: C, 62.27; H, 4.83; N, 2.96.
