Process for preparing substituted 2-arylethanols

#This application is a National Stage entry of International Application No. PCT/EP2017/050325, filed 9 Jan. 2017, which claims priority to European Patent Application No. 16151430.2, filed 15 Jan. 2016.

#The present invention relates to a process for preparing substituted 2-arylethanols, and to novel substituted 2-arylethanols.

#Substituted 2-arylethanols are important intermediates for the manufacture of bioactive compounds which can be used specifically for controlling pests in crop protection. In particular, they serve for the manufacture of insecticidal, acaricidal or herbicidal cyclic ketoenols (for example EP-A-456 063, EP-A-521 334, EP-A-596 298, EP-A-613 884, EP-A-613 885, WO 95/01 971, WO 95/26 954, WO 95/20 572, EP-A-0 668 267, WO 96/25 395, WO 96/35 664, WO 97/01 535, WO 97/02 243, WO 97/36 868, WO 97/43275, WO 98/05638, WO 98/06721, WO 98/25928, WO 99/24437, WO 99/43649, WO 99/48869, WO 99/55673, WO 01/17972, WO 01/23354, WO 01/74770, WO 03/013249, WO 03/062244, WO 04/007448, WO 04/024 688, WO 04/065366, WO 04/080962, WO 04/111042, WO 05/044791, WO 05/044796, WO 05/048710, WO 05/049569, WO 05/066125, WO 05/092897, WO 06/000355, WO 06/029799, WO 06/056281, WO 06/056282, WO 06/089633, WO 07/048545, WO 07/073856, WO 07/096058, WO 07/121868, WO 07/140881, WO 08/067873, WO 08/067910, WO 08/067911, WO 08/138551, WO 09/015801, WO 09/039975, WO 09/049851, WO 09/115262, WO 10/052161, WO 10/102758, WO 10/063378, WO 10/063670, WO 10/102758, WO 11/098443, WO 11/098440, WO 11/067135, WO 11/067240, WO 12/110519), where the substituted 2-arylethanols can be used to prepare the required substituted phenylacetic acids (WO 2013/080896).

#The compound of the formula (II) is also intended to include the other forms of the Schlenk equilibrium known to the person skilled in the art, with and without complexation of solvent molecules.

#Preference is given to the preparation of 2-arylethanols of the formula (I) in which R1, R5 independently of one another represent C1-C6-alkyl, C1-C6-fluoroalkyl having 1 to 13 fluorine atoms, optionally substituted C6-C10-aryl, fluorine, chlorine, a radical NR62, OR6 or SR6, where R6 represents C1-C6-alkyl, C1-C2-fluoroalkyl having 1 to 5 fluorine atoms or phenyl, R2, R3, R4 independently of one another represent hydrogen, C1-C6-alkyl, C1-C2-fluoroalkyl having 1 to 5 fluorine atoms, phenyl optionally substituted by C1-C4-alkyl, C1-C4-alkoxy, fluorine or chlorine, fluorine, chlorine or a radical OR6, where R6 represents C1-C6-alkyl, C1-C2-fluoroalkyl having 1 to 5 fluorine atoms or phenyl.

#Particular preference is given to the preparation of 2-arylethanols of the formula (I) in which R1, R5 independently of one another represent methyl, ethyl, n-propyl, iso-propyl, trifluoromethyl, phenyl optionally substituted by methyl, ethyl, n-propyl, iso-propyl, methoxy, ethoxy or fluorine, fluorine, chlorine or a radical OR6, where R6 represents methyl, ethyl, n-propyl, iso-propyl, n-butyl, tert-butyl, CHF2, CF3 or C2F5 and R2, R3, R4 independently of one another represent hydrogen, methyl, ethyl, n-propyl, iso-propyl, trifluoromethyl, phenyl optionally substituted by methyl, ethyl, n-propyl, iso-propyl, methoxy, ethoxy or fluorine, fluorine, chlorine or a radical OR6, where R6 represents methyl, ethyl, n-propyl, iso-propyl, n-butyl, tert-butyl, CHF2, CF3 or C2F5.