[CH:1]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[CH:4]=[CH:3][C:2]=1[CH:11]=O.[NH2:13][C:14]1[CH:22]=[CH:21][C:17]2[NH:18][N:19]=[N:20][C:16]=2[CH:15]=1.C([BH3-])#N.[Na+].C1C=C2C(C(O)(O)C(=O)C2=CC=1)=O.Cl.[OH-].[Na+]>CO.C(OCC)(=O)C.C(O)(=O)C>[NH:18]1[C:17]2[CH:21]=[CH:22][C:14]([NH:13][CH2:11][C:2]3[CH:3]=[CH:4][C:5]4[C:10](=[CH:9][CH:8]=[CH:7][CH:6]=4)[CH:1]=3)=[CH:15][C:16]=2[N:20]=[N:19]1The general procedure employed was as follows. Naphthalene-2-carbaldehyde (624 mg, 4 mmol) in methanol (25 ml) was added to a solution of 5-amino-1H-benzotriazole in methanol (25 ml) that had been adjusted to pH 6 by the addition of glacial acetic acid (1 ml). Sodium cyanoborohydride (1.89 g, 30 mmol) was added and the resulting mixture was stirred at room temperature overnight by which time TLC (A) and ninhydrin development indicated the conversion of starting materials. Hydrochloric acid (50% HCl/H2O, 5 ml) was added and the solution was neutralised to pH 7 by addition of NaOH (1M). Methanol was removed in vacuo to afford an aqueous residue that was dissolved in ethyl acetate (50 ml) and extracted with sodium chloride solution (4×20 ml). Purification by column chromatography, eluting with methanol (0-10%) in dichloromethane afforded [11] as a pale yellow oil. Trituration from diethyl ether afforded [11] as a white solid (880 mg, 80%). Rf (A) 0.42 δH(400 MHz; DMSO-d6 {D2O shake}) 4.50 (2H, s, CH2) 6.45 (1H, s, BT) 6.89 (1H, s, NH, disappeared) 6.91 (1H, d, J8.9, BT) 7.43-7.49 (2H, m, Ar—H) 7.54 (1H, d, J8.6, Nap) 7.65 (1H, d, J8.9, BT) 7.82-7.89 (4H, m, Nap) 14.72 (1H, s, NH, disappeared); m/z (EI−HR) 274.12177 [(M calc. for C17H14N4 274.12185].
Wird geladen…
