Method for preparing 3-trifluoromethyl chalcones

A method for preparing a compound of Formula 2

• wherein
• Z is phenyl optionally substituted with up to 5 substituents independently selected from R2;
• and
• each R2 is independently F, Cl, Br, C1-C6 alkyl, C1-C6 fluoroalkyl, C1-C6 alkoxy, C1-C6 fluoroalkoxy, C1-C6 alkylthio or C1-C6 fluoroalkylthio;
• comprising
• (1) forming a reaction mixture comprising a Grignard reagent derived from a compound of Formula 5
• Z—X 5
• wherein X is I,
• by contacting the compound of Formula 5 with
• (a) magnesium metal, or
• (b) an alkylmagnesium halide
• in the presence of an ethereal solvent;
• and then
• (2) contacting the reaction mixture with a compound of Formula 6
• wherein
• Y is OR11 or NR12R13;
• R11 is C1-C5 alkyl;
• and
• R12 and R13 are independently C1-C2 alkyl;
• or R12 and R13 are taken together as —CH2CH2OCH2CH2—.

A method for preparing a compound of Formula 7

• wherein
• Z is optionally substituted phenyl;
• and
• Q is phenyl or 1-naphthalenyl, each optionally substituted;
• using a compound of Formula 1
• characterized by:
• preparing said compound of Formula 1 by the method of claim 1.

A method for preparing a compound of Formula 7

• wherein
• Z is optionally substituted phenyl;
• and
• Q is phenyl or 1-naphthalenyl, each optionally substituted;
• using a compound of Formula 1
• characterized by:
• using as said compound of Formula 1 a compound of Formula 1 prepared by the method of claim 1.

A compound of Formula 2

• wherein
• Z is
• R2a is CF3;
• R2b is H or halogen;
• and R2c is halogen.