反应详情

A stirred solution of tosylate (34b) (200 mg, 0.46 mmol) and methylamine in ethanol (33% wt, 6 mL) was heated in a sealed pressure vessel at 150° C. for 72 hours. The mixture was then allowed to cool to ambient temperature then solvents removed in vacuo. The residue was dissolved in dichloromethane (20 mL), washed with water (15 mL) then dried (Na2SO4), filtered and reduced in vacuo. Flash chromatography over silica, eluting with dichloromethane:methanol mixtures 97:3 to 95:5 gave methylaminoalcohol (57) as a pale yellow solid (47 mg, 35%). TLC (Rf=0.22, DCM:MeOH 93:7), HPLC-MS 293.1 [M+H]+, 315.2 [M+Na]+, 607.3 [2M+Na]+; δH (500 MHz, CDCl3) mixture of rotamers major:minor 3:2; 2.42 (1.8H, s, NHCH3 major), 2.3 (1.2H, s, NHCH3 minor), 3.14-3.16 (1H, m, CHNHCH3), 3.35-4.48 (7H, m, OCH2CHOH, CHCHCHCH2NCbz), 5.06 and 5.22 (0.8H total, each d, J=12.22 Hz, Cbz minor), 5.12 (1.2H, s, Cbz major), 7.27-7.37 (5H, m, aromatic CH).

1. customsolvents removed in vacuo
2. dissolutionThe residue was dissolved in dichloromethane (20 mL)
3. washwashed with water (15 mL)
4. dry with materialthen dried (Na2SO4)
5. filtrationfiltered
6. washFlash chromatography over silica, eluting with dichloromethane