Patent ID: 6479661
Filing Date: 2002-11-12
Classification: C07C,C07D

Abstract:
A process for preparing a compound of formula (I), in whichR1 and R2 are, each independently, H, A, Ar, â€”Si (R6)3, â€”Sn (R6)3, â€”SR7, â€”OR7 or â€”NR8R9, R3 is H, R4 and R5 are, each independently, A, Ar, â€”Si (R6)3, â€”Sn (R6)3, â€”SR7, â€”OR7 or â€”NR8R9, R6, R7, R8 and R9 are each independently A or Ar, A is a straight-chain or branched alkyl radical of 1 to 10 C atoms, a straight-chain or branched alkenyl radical of 2 to 10 C atoms, a substituted or unsubstituted cycloalkyl radical of 3 to 8 C atoms, or a mono- or polyunsaturated cycloalkyl radical of 3 to 8 C atoms, and Ar is a substituted or unsubstituted aryl radical having 6 to 20 C atoms, wherein R1 and R2 or R8 and R9 optionally form a cyclic ring having 3 to 8 C atoms which optionally has, in addition to one nitrogen atom, at least one heteroatom of â€”Sâ€”, â€”Oâ€” orâ€”NR6â€”;with the proviso that the radicals R4 and R5 have at most one hydrogen atom in the &bgr; position, or either one or both of R4 and R5 are cyclopropyl,said process comprising reacting a compound of formula (II) in which R1, R2 and R3 have the meanings given above,with a reagent of formula (III) in a solventZâ€”R4â€ƒâ€ƒ(III) in whichR4 has the meaning given above, Z is Li or MgX, X is Hal, and Hal is Cl, Br or I, and with an organotitanate of formula (IV)R5TiX3âˆ’n(OR)n in whichR5 has the meaning given above, X is Cl, Br or I, R is alkyl having 1 to 10 C atoms or aryl having 6 to 20 C atoms, and n is an integer of 1 to 3.