Prepn. of 2-substd. tri:fluoro:methoxy:benzene derivs. - by reaction of e.g. corresp. unsubstd. cpd. with strong base, followed by reaction with electrophile

摘要

Prepn. of 2-substd. trifluoromethoxylenzene derivs. of formula (I) comprises reaction of an unsubstd.- or 4-substd. trifluoromethoxybenzene deriv. with a strong base followed by reaction of the resultant or the anion with an electrophile: T = hal or R1; R1 = H, 1-20C alkyl, 1-20C alkoxy, 2-20C alkenyl, or a mesogenic gp. of formula R1-A1-Z1-(A2-Z2)m-; R5 = H, or 1-15C alkyl, 2-15C alkenyl (in both of which one or more CH2 gps. are opt. replaced by S or O, provided that such O or S atoms are not neighbouring); A1,A2 = trans-1,4-cyclohexylene (which is opt. substd. by CN or hal and in which one or more non-neighbouring CH2 gps. are opt. replaced by O and/or S), 1,4-phenylene (which is opt. substd. by CN or halo and in which 1-2 CH gps. are opt replaced by N), 1,4-cyclohexenylene, 1-4-bicyclo(2,2,2)octylene, piperidin-1,4-diyl, naphthalen-2,6-diylo, decahydronaphthalen-2,6-diyl or 1,2,3,4-tetrahydronaphthalen-2,6-diyl; Z1,Z2 = CH2O, OCH2, CH2S, SCH2, CH2CH2, CH=CH, C=C or a bond; m = 0,1 or 2; X = hal, SH, Si(R2)3, B(OR3)2, R4, COOH, COR4 or CH(OH)R4; R2,R3 = H, alkyl or 1-12C aryl; R4 = 1-8C alkyl, or 2-8C alkenyl. USE/ADVANTAGE - (I) are intermediates in prodn. of liquid crystals, plant protectants or pharmaceuticals (e.g. antimaterial cpds.) or, in some cases, may themselves be useful as these agents. The process gives (I) in high yeild and is simple.