Methanesulfonic Acid → Methyl 4-[(2r)-2-({[(2s)-2-hydroxy-3-phenoxypropyl]amino}methyl)-3,4-dihydro-2h-chromen-6-yl]benzoate methanesulfonate

Temperature

40 °C

In a 500-mL three-neck round bottom flask was dissolved K2CO3 (37.3 g, 270 mmol, 3.8 eq.) in 120 mL water. (2S)-1-(benzyl{[(2R)-6-bromo-3,4-dihydro-2H-chromen-2-yl]methyl}amino)-3-phenoxy-2-propanol hydrobromide (Example 86, 40 g, 180 mmol, 1.0 eq.) was then added. To the resulting suspension was then added 130 mL isopropanol, p-carbomethoxyphenyl boronic acid (20.5 g, 114 mmol, 1.6 eq.) and 10% Pd/C (3.77 g, 1.78 mmol, 0.025 eq.). The resulting suspension was heated at reflux for 4 hours, cooled to 40° C., and 159 mL ethylacetate was added. This suspension was heated to 50° C. and filtered and washed with 100 mL warm (55° C.) ethylacetate. The filtrate separated to two phases. The aqueous phase was separated, and the organic phase was transferred to a 1-L three-neck round bottom flask, to which was added 300 mL ethyl acetate, 10% Pd-C (7.2 g, 0.89 mmol, 0.05 eq.) and a solution of sodium formate (14.4 g, 211 mmol, 3.0 eq.) in 80 mL water. The resulting suspension was refluxed for 6 hours. Methanesulfonic acid (28 g, 146 mmol, 4.1 eq.) was added to the reaction at a temperature ≧50° C. The resulting suspension was filtered; the organic filtrate was separated and washed with 60 mL water. The organics were distilled to half of the original volume, cooled and methyl 4-[(2R)-2-({[(2S)-2-hydroxy-3-phenoxypropyl]amino}methyl)-3,4-dihydro-2H-Chromen-6-yl]benzoate methanesulfonate filtered and washed with ethylacetate. The dry white crystalline product (15.5 g, 80% yield) was used without further purification. NMR (DMSO-d6) δ1.77 (m, 1H), 2.10 (m 1H), 2.42 (s, 3H, HSO3CH3), 2.90 (m, 2H), 3.12 (dd, J=8, 1.8 Hz, 1H), 3.36 (m, 2H), 3.85) (s, 3H), 4.02 (m, 2H), 4.25 (m, 1H), 4.50 (tt, J=7, 1.5 Hz, 1H), 5.87 (bs, 1H, OH), 6.95 (m, 4H, ArH), 7.33 (t, J=7 Hz, 2H, ArH), 7.52 (m, 2H, ArH), 7.77 (d, J=8 Hz, 2H, ArH), 7.95 (d, J=8 Hz, 2H, ArH); MS (EI): m/z 448 (MH+).

1. temperatureThe resulting suspension was heated
2. temperatureat reflux for 4 hours
3. temperatureThis suspension was heated to 50° C.
4. filtrationfiltered
5. washwashed with 100 mL
6. temperaturewarm (55° C.) ethylacetate
7. customThe filtrate separated to two phases
8. customThe aqueous phase was separated
9. customthe organic phase was transferred to a 1-L three-neck round bottom flask, to which
10. temperatureThe resulting suspension was refluxed for 6 hours
11. filtrationThe resulting suspension was filtered
12. customthe organic filtrate was separated
13. washwashed with 60 mL water
14. distillationThe organics were distilled to half of the original volume
15. temperaturecooled
16. filtrationmethyl 4-[(2R)-2-({[(2S)-2-hydroxy-3-phenoxypropyl]amino}methyl)-3,4-dihydro-2H-Chromen-6-yl]benzoate methanesulfonate filtered
17. washwashed with ethylacetate

ORD record

ord-2ccf3f0180cb417d82ce7bd4ce089834

Source dataset

uspto-grants-2004_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06699860B2