合成路线1

The diazotation of 2,3-dichloroaniline (IX) with NaNO2 and HCl gives the corresponding diazonium chloride (X), which by a Sandmeyer reaction with CuCN yields 2,3-dichlorophenyl cyanide (XI). The Grignard reaction of (XI) with methylmagnesium bromide (A) in ether affords 2,3-dichloroacetophenone (XII), which by a Willgerodt reaction with S and morpholine is converted into 2,3-dichlorophenylacetic acid (XIII). The reaction of (XIII) with oxalyl chloride (B) in carbon tetrachloride affords the corresponding acyl chloride (XIV), which is cyclized with ethylene (C) by means of AlCl3 in methylene chloride yielding 7,8-dichloro-2-tetralone (XV). The reaction of (XV) with sodium azide in CHCl3 by means of H2SO4 gives 8,9-dichloro-2-benzazepin-3-one (XVI), which is finally reduced with diborane in THF.