薛大泉, 张 威, 邓泽军, 马红梅, 郑 实, 虞心红
(1. 华东理工大学 a. 化工学院; b. 药学院,上海 200237)
达泊西汀[1,化学名(S)-(+)-(N,N-二甲氨基)-3-(萘基-1-氧基)苯丙胺]是一种选择性5-羟色胺重摄取抑制剂,临床上用其盐酸盐[1]。2009年2月在芬兰和瑞典上市,用于成年男子早泄的按需治疗,成为第一个改善男性早泄的新药[2]。1的半衰期短,不良反应小,能有效控制早泄症状[3]。预计1的年销售额可达到5亿美元[4]。
目前合成1的方法,要么合成路线较长,需要拆分,且收率不高[5~8];或原料昂贵且不易得,操作复杂[11~16];以3-氯苯丙酮为起始原料,经不对称还原,烃化,O-甲磺酰化及二甲胺化和成盐合成1[17,18],此方法原料易得,操作简单,且避免了拆分,具有良好的工业化前景,不足之处在于不对称还原收率偏低。
本文借鉴合成手性醇的方法[19],由硼氢化钠-无水氯化亚锡-(S)-(-)-α,α-二苯基脯氨醇不对称还原体系成功地将3-氯苯丙酮还原成(R)-(+)-3-氯苯丙醇(2, Scheme 1),对映选择性高,收率93.6%,弥补了文献[17,18]方法的不足。
X0-6型精密熔点仪(温度计未经校正);WYS-300型核磁共振仪(CDCl3为溶剂,TMS为内标),VG ZAB-2fz型质谱仪。
Scheme1
柱色谱用硅胶H或50 μm~75 μm硅胶、薄层色谱用硅胶GF254,青岛海洋化工厂;其余所用试剂均为分析纯。
(1) 2的合成
(2) (R)-(-)-3-(1-萘氧基)-1-苯基-1-丙醇(3)的合成
在三口烧瓶中加入固体NaOH 0.41 g(10.3 mmol)和DMF 8 mL,冰浴冷却至3 ℃~5 ℃,搅拌下滴加α-萘酚1.39 g(9.64 mmol)的DMF(4 mL)溶液,滴毕,于5 ℃左右反应2 h;加入2 1.50 g(8.79 mmol)的DMF(4 mL)溶液,于室温反应30 h(TLC跟踪)。搅拌下倾入冰水(40 mL)中析晶,过滤,滤饼用水洗至近中性,于50 ℃减压干燥后用石油醚重结晶得白色固体3,收率68.0%, m.p.77.2 ℃~78.1 ℃(67%, 76 ℃~78 ℃[17]);1H NMRδ: 8.27(dd,J=3.4 Hz, 6.1 Hz, 1H, ArH), 7.84(dd,J=3.3 Hz, 6.1 Hz, 1H, ArH), 7.33~7.53(m, 9H, ArH, PhH), 6.83(d,J=7.6 HZ, 1H, ArH), 5.16~5.20(m, 1H, 1-H), 4.21~4.41(m, 2H, 3-H), 2.39~2.45(m, 2H, 2-H), 1.28(s, 1H, OH); EI-MSm/z: 278.2(M+)。
(3) 1·HCl的合成
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