1. Mirtazapine having a mean particle diameter of less than 200 micrometer.
2. Mirtazapine of claim 1 wherein the mean particle diameter of less than 100 micrometer.
3. Mirtazapine of claim 2 wherein the mean particle diameter of less than about 20 micrometer.
4. Mirtazapine of claim 3 wherein the mean particle diameter is about 10 micrometer.
5. Mirtazapine of claim 1 wherein the mean particle size of less than 100 micrometers and greater than 10 micrometers.
6. A process for preparing micronized mirtazapine, which comprises micronizing mirtazapine.
7. The process according to claim 6 wherein the mirtazapine that is to be micronized is purified mirtazapine
8. The process according to claim 6 in which the mirtazapine that is to be micronized is dry mirtazapine.
9. The process of claim 6 wherein the mirtazapine that is to be micronized has a mean particle diameter of about 300 microns.
10. The process of claim 6 wherein the mirtazapine that is to be micronized has a mean particle diameter of about 250 microns.
11. Mirtazapine with a mean diameter of about 10 microns.
12. A pharmaceutical composition comprising a therapeutically effective amount micronized mirtazapine as claimed in any of claims 1 and 11.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A process comprising
a) contacting an unsaturated compound containing aliphatic carbon-carbon double bonds with a quaternary ammonium tribromide or a quaternary phosphonium tribromide in the presence of at least one solvent for the unsaturated compound under conditions such that the unsaturated compound becomes brominated and, as a by-product, (1) a mixture of a quaternary ammonium monobromide salt and a quaternary ammonium monochloride salt or (2) a mixture of a quaternary phosphonium monobromide salt and a quaternary phosphonium monochloride salt is formed,
b) separating the quaternary ammonium monochloride salt or quaternary phosphonium monochloride salt from the brominated unsaturated compound, then
c) contacting a solution of said separated quaternary ammonium or quaternary phosphonium monochloride salt with a source of bromide ions under conditions that at least a portion of the quaternary ammonium or quaternary phosphonium monochloride salt reacts with said source of bromide ions to regenerate a quaternary ammonium monobromide salt or quaternary phosphonium monobromide salt and a chloride by-product;
d) contacting the regenerated quaternary ammonium monobromide salt or regenerated quaternary phosphonium monobromide salt with bromine to form the corresponding quaternary ammonium tribromide or quaternary phosphonium tribromide; and then
e) before, during or after step d), separating the chloride by-product from the regenerated quaternary ammonium or quaternary phosphonium monobromide salt or quaternary ammonium or quaternary phosphonium tribromide and then
f) recycling quaternary ammonium tribromide or quaternary phosphonium tribromide obtained in step d) back into step a).
2. The process of claim 1, wherein the solvent for the unsaturated compound is chlorinated.
3. The process of claim 1, wherein the source of bromide ions is an alkali metal bromide, an alkaline earth metal bromide; hydrogen bromide, a hydrobromic acid solution; an organic amine hydrobromide salt or an organic phosphine hydrobromide salt.
4. The process of claim 1, wherein step e) is performed before step d).
5. The process of claim 1, wherein the unsaturated compound is a homopolymer or copolymer of butadiene.
6. The process of claim 1, wherein the brominated unsaturated compound contains 500 ppm or less of chlorine.
7. The process of claim 2, wherein the source of bromide ions is an alkali metal bromide, an alkaline earth metal bromide; hydrogen bromide, a hydrobromic acid solution; an organic amine hydrobromide salt or an organic phosphine hydrobromide salt.
8. The process of claim 7, wherein step e) is performed before step d).
9. The process of claim 8, wherein the unsaturated compound is a homopolymer or copolymer of butadiene.
10. The process of claim 9, wherein the brominated unsaturated compound contains 500 ppm or less of chlorine.