C1(N=C=NC2CCCCC2)CCCCC1.[C:16](=[S:18])=S.[C:19]([O:22][C:23]1[C:24]([C:39]([CH3:42])([CH3:41])[CH3:40])=[CH:25][C:26]2[O:30][C:29]([CH2:32][NH2:33])([CH3:31])[CH2:28][C:27]=2[C:34]=1[C:35]([CH3:38])([CH3:37])[CH3:36])(=[O:21])[CH3:20]>O1CCCC1>[C:19]([O:22][C:23]1[C:24]([C:39]([CH3:42])([CH3:41])[CH3:40])=[CH:25][C:26]2[O:30][C:29]([CH2:32][N:33]=[C:16]=[S:18])([CH3:31])[CH2:28][C:27]=2[C:34]=1[C:35]([CH3:38])([CH3:37])[CH3:36])(=[O:21])[CH3:20]To an ice-cooled suspension of 4.56 g of dicyclohexylcarbodiimide and 8 ml of carbon disulfide in 20 ml of tetrahydrofuran was added dropwise a solution of 6.18 g of 5-acetoxy-2-aminomethyl-4,6-di-t-butyl-2-methyl-2,3-dihydrobenzofuran synthesized in Example 70-5) in 20 ml of tetrahydrofuran. The mixture was stirred at 0° C. for 2 hours and then stirred at room temperature for 24 hours. After reaction, carbon disulfide and tetrahydrofuran were removed using an evaporator and the precipitated dicyclohexylthiourea was filtered off. Then, water was added to the filtrate and the solution was extracted with ethyl acetate. The organic layer was washed with saturated brine, dried over anhydrous magnesium sulfate, and then concentrated. The concentrate was purified by silica gel column chromatography eluting with n-hexane containing 10% ethyl acetate to give 5.15 g of (5-acetoxy-4,6-di-t-butyl-2-methyl-2,3-dihydrobenzofuran-2-yl)methyl isothiocyanate (rotamer mixture) as a colorless oil (yield 74%).
読み込み中…
