The present invention provides a process for the preparation of a 5-substituted-1-(4-fluorophenyl)-1,3-dihydro-isoben-zofuran of Formula (2), an intermediate for the manufacture of citalopram, which process comprises: (a) carrying out a Grignard reaction on a corresponding 5-substituted phthalide of Formula (3) in a co-solvent system, comprising adding (i) prepared 4-fluorophenyl magnesium halide in an ether solvent to (ii) the 5-substituted phthalide in a suitable organic co-solvent to the ether solvent, to form a corresponding 4-substituted-2-hydroxymethyl-4′-fluorobenzophenone of Formula (4); (b) carrying out a ketone reduction of the 4-substituted-2-hydroxymethyl-4′-fluorobenzophenone of Formula (4) following the Grignard reaction, to form a corresponding 4-substituted-2-hydroxymethylphenyl-1-(4-fluorophenyl) methanol of Formula (5); and (c) carrying out a cyclisation reaction on the 4-substituted-2 hydroxymethylphenyl-1-(4-fluorophenyl) methanol of Formula (5) following the reduction reaction, to form said intermediate of Formula (2); wherein R represents Br or CN.
本发明提供一种制备5-取代-1-(4-
氟苯基)-
1,3-二氢异苯并呋喃(式(2))的过程,该过程是制造
舍曲林的中间体,包括以下步骤:(a)在共溶剂体系中对应的5-取代邻苯二酸酐(式(3))进行
格氏试剂反应,包括将(i)制备的4-
氟苯基
镁卤化物在醚溶剂中加入(ii)适当的有机共溶剂到醚溶剂中的5-取代邻苯二酸酐,形成相应的4-取代-2-羟甲基-4'-
氟苯基苯甲酮(式(4));(b)在
格氏试剂反应后对式(4)中的4-取代-2-羟甲基-4'-
氟苯基苯甲酮进行酮还原反应,形成相应的4-取代-2-羟甲基苯基-1-(4-
氟苯基)
甲醇(式(5));(c)在还原反应后对式(5)中的4-取代-2-羟甲基苯基-1-(4-
氟苯基)
甲醇进行环化反应,形成所述的中间体(式(2));其中R代表Br或CN。