Crystal form of N-(4-trifluoromethylphenyl)-5-methylisoxazole-4-carboxamide

A process for the conversion of a second crystal modification to a first crystal modification having the formula I

• 4
• wherein said first crystal modification has an X-ray diffraction pattern obtained with a focusing Debye-Scherrer beam and Cu—Kα1-radiation, has lines at the following diffraction angles 2θ:
• Lines of strong intensity:
• 10.65;
• 14.20;
• 14.80;
• 16.10;
• 21.70;
• 23.15;
• 24.40;
• 24.85;
• 25.50;
• 25.85;
• 26.90;
• and 29.85 degrees,
• Lines of medium intensity:
• 7.40;
• 9.80;
• 13.10;
• 15.45;
• 16.80;
• 20.70;
• 21.45;
• 22.80;
• 23.85;
• 27.25;
• and 28.95 degrees,
• wherein said second crystal modification of the formula I has the X-ray diffraction pattern (Cu—Kα1) with characteristic lines at the following diffraction angles 2θ:
• Lines of strong intensity:
• 16.70;
• 18.90;
• 23.00;
• 23.65;
• and 29.05 degrees;
• Lines of medium intensity:
• 8.35;
• 12.65;
• 15.00;
• 15.30;
• 18.35;
• 21.25;
• 22.15;
• 24.10;
• 24.65;
• 25.45;
• 26.65;
• 27.40;
• 28.00;
• and 28.30 degrees, comprising the steps of:
• (a) placing the second crystal modification or a mixture of the first and second crystal modifications in a solvent to form a solution;
• and
• (b) abruptly cooling the solution to between about −5° C. to about −25° C. to form crystals.

A process for the conversion of a second crystal modification to a first crystal modification of formula I

• 5
• wherein said first crystal modification has an X-ray diffraction pattern obtained with a focusing Debye-Scherrer beam and Cu—Kα1-radiation, has lines at the following diffraction angles 2θ:
• Lines of strong intensity:
• 10.65;
• 14.20;
• 14.80;
• 16.10;
• 21.70;
• 23.15;
• 24.40;
• 24.85;
• 25.50;
• 25.85;
• 26.90;
• and 29.85 degrees,
• Lines of medium intensity:
• 7.40;
• 9.80;
• 13.10;
• 15.45;
• 16.80;
• 20.70;
• 21.45;
• 22.80;
• 23.85;
• 27.25;
• and 28.95 degrees,
• wherein said second crystal modification of the formula I has the X-ray diffraction pattern (Cu—Kα1) with characteristic lines at the following diffraction angles 2θ:
• Lines of strong intensity:
• 16.70;
• 18.90;
• 23.00;
• 23.65;
• and 29.05 degrees;
• Lines of medium intensity:
• 8.35;
• 12.65;
• 15.00;
• 15.30;
• 18.35;
• 21.25;
• 22.15;
• 24.10;
• 24.65;
• 25.45;
• 26.65;
• 27.40;
• 28.00;
• and 28.30 degrees, comprising the steps of:
• (a) placing the second crystal modification or mixtures of the first and second crystal modifications in a solvent to form a solution;
• and
• (b) heating the solution to between about 10° C. and about 40° C.

A process for the conversion of a first crystal modification to a second crystal modification of a formula I

• 6
• wherein said first crystal modification has an X-ray diffraction pattern obtained with a focusing Debye-Scherrer beam and Cu—Kα1-radiation, has lines at the following diffraction angles 2θ:
• Lines of strong intensity:
• 10.65;
• 14.20;
• 14.80;
• 16.10;
• 21.70;
• 23.15;
• 24.40;
• 24.85;
• 25.50;
• 25.85;
• 26.90;
• and 29.85 degrees,
• Lines of medium intensity:
• 7.40;
• 9.80;
• 13.10;
• 15.45;
• 16.80;
• 20.70;
• 21.45;
• 22.80;
• 23.85;
• 27.25;
• and 28.95 degrees,
• wherein said second crystal modification of the formula I has the X-ray diffraction pattern (Cu—Kα1) with characteristic lines at the following diffraction angles 2θ:
• Lines of strong intensity:
• 16.70;
• 18.90;
• 23.00;
• 23.65;
• and 29.05 degrees;
• Lines of medium intensity:
• 8.35;
• 12.65;
• 15.00;
• 15.30;
• 18.35;
• 21.25;
• 22.15;
• 24.10;
• 24.65;
• 25.45;
• 26.65;
• 27.40;
• 28.00;
• and 28.30 degrees, comprising the steps of:
• (a) placing the first crystal modification or mixtures of the first and second crystal modifications in a solvent to form a solution;
• and
• (b) forming crystals of the second crystal modification at elevated temperatures.

A process for the conversion of a first crystal modification to a second crystal modification of a formula I

• 7
• wherein said first crystal modification has an X-ray diffraction pattern obtained with a focusing Debye-Scherrer beam and Cu—Kα1-radiation, has lines at the following diffraction angles 2θ:
• Lines of strong intensity:
• 10.65;
• 14.20;
• 14.80;
• 16.10;
• 21.70;
• 23.15;
• 24.40;
• 24.85;
• 25.50;
• 25.85;
• 26.90;
• and 29.85 degrees,
• Lines of medium intensity:
• 7.40;
• 9.80;
• 13.10;
• 15.45;
• 16.80;
• 20.70;
• 21.45;
• 22.80;
• 23.85;
• 27.25;
• and 28.95 degrees,
• wherein said second crystal modification of the formula I has the X-ray diffraction pattern (Cu—Kα1) with characteristic lines at the following diffraction angles 2θ:
• Lines of strong intensity:
• 16.70;
• 18.90;
• 23.00;
• 23.65;
• and 29.05 degrees;
• Lines of medium intensity:
• 8.35;
• 12.65;
• 15.00;
• 15.30;
• 18.35;
• 21.25;
• 22.15;
• 24.10;
• 24.65;
• 25.45;
• 26.65;
• 27.40;
• 28.00;
• and 28.30 degrees, comprising the steps of:
• (a) collecting solid second crystal modification or a mixture of solid second crystal modification and solid first crystal modification;
• and
• (b) heating the solid second crystal modification or solid first crystal modification and solid second crystal modification of step (a) to a temperature of about 50° C. to about 130° C.

A process for the conversion of a first crystal modification to a second crystal modification of a formula I

• 8
• wherein said first crystal modification has an X-ray diffraction pattern obtained with a focusing Debye-Scherrer beam and Cu—Kα1-radiation, has lines at the following diffraction angles 2θ:
• Lines of strong intensity:
• 10.65;
• 14.20;
• 14.80;
• 16.10;
• 21.70;
• 23.15;
• 24.40;
• 24.85;
• 25.50;
• 25.85;
• 26.90;
• and 29.85 degrees,
• Lines of medium intensity:
• 7.40;
• 9.80;
• 13.10;
• 15.45;
• 16.80;
• 20.70;
• 21.45;
• 22.80;
• 23.85;
• 27.25;
• and 28.95 degrees,
• wherein said second crystal modification of the formula I has the X-ray diffraction pattern (Cu—Kα1) with characteristic lines at the following diffraction angles 2θ:
• Lines of strong intensity:
• 16.70;
• 18.90;
• 23.00;
• 23.65;
• and 29.05 degrees;
• Lines of medium intensity:
• 8.35;
• 12.65;
• 15.00;
• 15.30;
• 18.35;
• 21.25;
• 22.15;
• 24.10;
• 24.65;
• 25.45;
• 26.65;
• 27.40;
• 28.00;
• and 28.30 degrees, comprising the steps of:
• (a) placing crystals of said first crystal modification or a mixture of the first crystal modification and said second crystal modification into an organic solvent or into mixtures of organic solvents and water to form a solution;
• (b) heating the solution to a temperature of greater than about 40° C. to about the boiling point of the organic solvent;
• (c) diluting the solution with water, or distilling of the organic solvent, so that the organic solvent and water are present in a ratio of from about 4:1 to about 0.3:1;
• and
• (d) heating the solution to a temperature of above about 40° C. until crystals of the second crystal modification form.