Synthesis of Isobenzofuran Derivatives as heterocyclic analogues of the herbicidesindone B
摘要:
The target compounds 21-27 were synthesized via bromination of the N,N,1,1-tetramethylisobenzofuranamines 13, 15 and 16, subsequent bromine-lithium exchange and reaction with propanal or propanoyl chloride, respectively. In the course of some model reactions undertaken to test a synthetic strategy based on directed ortho-lithiation governed by the dimethylamino-group a useful synthesis of the ketone 3 was developed.
Synthese neuer N, N,1,1-Tetramethyl-isobenzofuranamine
摘要:
The nitrophthalides 3 a - d aimed as intermediates in the synthesis of the title compounds 6 a - d were obtained via regioselective reduction of 3-nitro-phthalic anhydride 1 or by nitration of phthalide and 3,3-dimethylphthalide, respectively. Reductive methylation of the nitro groups afforded the dimethylaminophthalides 5 a - d which in turn were reacted with MeMgI or in the case of 5 d reduced by LiAlH4 leading finally to the title compounds.