[CH:1]([N-:4][CH:5](C)C)(C)[CH3:2].[Li+].[Li]CCCC.C([NH:17]C(C)C)(C)C.CC1[O:26]N=CC=1.N[O:28][C:29]1[CH2:35][CH2:34][CH2:33][CH2:32][CH2:31][CH:30]=1>C1COCC1>[OH2:26].[NH2:17][C:1]1[N:4]2[CH2:5][CH2:30][CH2:31][CH2:32][CH2:33][C:34]2=[CH:35][C:29](=[O:28])[CH:2]=1
To a solution of lithium diisopropylamide (LDA), prepared from n-BuLi (125 ml, 0.2M) and diisopropylamine (20.2 g, 28.1 ml, 0.2M) in dry THF (100 ml) was added under N2 at -30° to -10° C., 5-methylisoxazole (8.3 g, 0.1M). The resultant yellow suspension was mechanically stirred at -10° C. for 1 hr before 1-aza-2-methoxy-1-cycloheptene (12.7 g, 0.1M) was added dropwise. After the addition was complete, a yellow solid separated and the mixture was allowed to warm to ambient over a period of 19 hr. Then dry MeOH (50 ml) was slowly added and the resultant reddish solution was vigorously stirred at ambient for 2 hr and filtered through a silica gel pad. The filtrate was evaporated in vacuo, and the residual oil was flash column chromatographed on silica gel (EM-60) with 30% MeOH in CH2Cl2 as the eluent to give the desired amine, which was further recrystallized from MeOH/Et2O to give the title compound (5.75 g, 30%), mp>230° C. TLC (30% MeOH in CH2Cl2): Rf=0.40. IR (KBr) cm-1, 3400-3200 (broad), 1660, 1635.
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