作者:John M Mellor、Afaf H El-Sagheer、El-Sayed H El-Tamany、Reda N Metwally
DOI:10.1016/s0040-4020(00)00977-7
日期:2000.12
2-trifluoro-1-ethanone with benzylic Grignard reagents affords by 1,2-addition unsaturatedallylic alcohols. These alcohols readily undergo dehydration and cyclisation to give trifluoromethylnaphthalenes. The generality of this procedure was established by reaction with diverse benzyl and allyl Grignard reagents and by reaction of a number of unsaturated ketones. The resulting trifluoromethylnaphthalenes were oxidised
Reaction of Benzyl Grignard Reagents with Trifluoroacetyldihydropyrans and Other Cyclic β-Alkoxy-α,β-Unsaturated Trifluoromethylketones
作者:Simon J Coles、John M Mellor、Afaf H El-Sagheer、Ezz El-Din M Salem、Reda N Metwally
DOI:10.1016/s0040-4020(00)00976-5
日期:2000.12
Benzyl Grignard reagents react with cyclic β-alkoxy-α,β-unsaturated trifluoromethyl ketones by 1,2-addition to afford unsaturated allylic alcohols in high yield. The factors determining the balance between 1,2- and 1,4-addition to unsaturated ketones are discussed. The structures of major and minor products are established by single crystal X-ray diffraction studies.
A synthesis of trifluoromethyl-substituted naphthalenes
作者:John M Mellor、Afaf H El-Sagheer、Ezz El-Din M Salem
DOI:10.1016/s0040-4039(00)01254-5
日期:2000.9
Alkyl and aryl Grignard reagents add to 1-(3,4-dihydro-2H-5-pyranyl)-2,2,2-trifluoro-1-ethanone by 1,4-addition, but benzyl Grignard reagents react in good yield by 1,2-addition. Dehydration of the resulting alcohols affords intermediate dienes, which readily undergo cyclisation to give substituted trifluoromethylnaphthalenes. Addition to other trifluoromethylketones permits access to a range of novel fluorinated naphthalenes and benzenes. (C) 2000 Published by Elsevier Science Ltd.