| 摘要 |
1343485 Substituted dibenzofurans and dibenzothiophenes SANDOZ Ltd 19 April 1971 [13 March 1970] 21913/71 Heading C2C [Also in Division C3] The invention comprises compounds (I), where the nuclei A and B may be optionally substituted by alkyl; m is 1 or 2; n is 1, 2 or 3; X is oxygen or sulphur; R 1 is C 4-8 tertiary alkyl; and R 2 is hydrogen or optionally substituted alkyl or cycloalkyl, and their preparation by reacting a compound (II) with m+n-1 moles of a compound (IV) in which Y is halogen, hydroxy or C 1-6 alkoxy, in the presence of an acid catalyst or by reacting a compound (V) with m+n-1 moles of a compound (III) or (VI), in which Z 1 is halogen and M is Li, Na or K. Tert.butyldibenzo[b,d]furan is made by reacting dibenzofuran with t.butyl chloride in the presence of AlCl 3 . A dibenzo[b,d]furan 'substituted in the benzene nuclei by@1-3 chloromethyl groups is made by reacting dibenzofuran with formaldehyde and SOCl 2 in the presence of ZnCl 2 . |
