Reaction SMILES: [CH3:1][S:2](Cl)(=[O:4])=[O:3].[Cl:6][C:7]1[N:12]=[C:11]([CH2:13][OH:14])[CH:10]=[C:9]([N:15]2[CH2:20][CH2:19][O:18][CH2:17][C@H:16]2[CH3:21])[N:8]=1.C(N(CC)CC)C>C(Cl)Cl>[CH3:1][S:2]([O:14][CH2:13][C:11]1[CH:10]=[C:9]([N:15]2[CH2:20][CH2:19][O:18][CH2:17][C@H:16]2[CH3:21])[N:8]=[C:7]([Cl:6])[N:12]=1)(=[O:4])=[O:3]
Reactant: CS(=O)(=O)Cl
Reactant: C[C@@H]1COCCN1c1cc(CO)nc(Cl)n1
Solvent: ClCCl
Solvent: CCN(CC)CC
Product: C[C@@H]1COCCN1c1cc(COS(C)(=O)=O)nc(Cl)n1
Temperature: 25 °C
Reaction time: 1.5 h
Yield: 104.9 %

Procedure:
(R)-3-methylmorpholine (7.18 g, 71.01 mmol) and triethylamine (12.87 ml, 92.31 mmol) were added to methyl 2,4-dichloropyrimidine-6-carboxylate (14.70 g, 71.01 mmol) in DCM (100 ml). The resulting mixture was stirred at RT for 18 hours. Water (100 ml) was added, the layers separated and extracted with DCM (3×75 ml). The combined organics were dried over MgSO4, concentrated in vacuo and the residue triturated with Et2O to yield (R)-methyl 2-chloro-6-(3-methylmorpholino)pyrimidine-4-carboxylate (14.77 g, 77%); 1H NMR (400 MHz, CDCl3) 1.35 (3H, d), 3.34 (1H, td), 3.55 (1H, td), 3.70 (1H, dd), 3.81 (1H, d), 3.97 (3H, s), 4.03 (1H, dd), 4.12 (1H, br s), 4.37 (1H, br s), 7.15 (1H, s); m/z: (ESI+) MH+, 272.43. The liquors were concentrated onto silica and purified by chromatography on silica eluting with a gradient of 20 to 40% EtOAc in isohexane. Fractions containing product were combined and evaporated to afford (R)-methyl 2-chloro-6-(3-methylmorpholino)pyrimidine-4-carboxylate (1.659 g, 9%); 1H NMR (400 MHz, CDCl3) 1.35 (3H, d), 3.33 (1H, td), 3.55 (1H, td), 3.69 (1H, dd), 3.80 (1H, d), 3.97 (3H, s), 4.03 (1H, dd), 4.12 (1H, br s), 4.36 (1H, br s), 7.15 (1H, s); m/z: (ESI+) MH+, 272.43. b) Lithium borohydride, 2M in THF (18 ml, 36.00 mmol) was added dropwise to (R)-methyl 2-chloro-6-(3-methylmorpholino)pyrimidine-4-carboxylate (16.28 g, 59.92 mmol) in THF (200 ml) at 0° C. over a period of 20 minutes under nitrogen. The resulting solution was stirred at 0° C. for 30 minutes and then allowed to warm to RT and stirred for a further 18 hours. Water (200 ml) was added and the THF evaporated. The aqueous layer was extracted with EtOAc (2×100 ml) and the organic phases combined, dried over MgSO4 and then evaporated to afford (R)-(2-chloro-6-(3-methylmorpholino)pyrimidin-4-yl)methanol (14.54 g, 100%) which was used in the next step without purification; 1H NMR (400 MHz, CDCl3) 1.32 (3H, d), 2.65 (1H, br s), 3.25-3.32 (1H, m), 3.51-3.57 (1H, m), 3.67-3.70 (1H, m), 3.78 (1H, d), 3.98-4.09 (2H, m), 4.32 (1H, br s), 4.59 (2H, s), 6.44 (1H, s); m/z: (ESI+) MH+, 244.40. c) Methanesulfonyl chloride (4.62 ml, 59.67 mmol) was added dropwise to (R)-(2-chloro-6-(3-methylmorpholino)pyrimidin-4-yl)methanol (14.54 g, 59.67 mmol) and triethylamine (8.32 ml, 59.67 mmol) in DCM (250 ml) at 25° C. over a period of 5 minutes. The resulting solution was stirred at 25° C. for 90 minutes. The reaction mixture was quenched with water (100 ml) and extracted with DCM (2×100 ml). The organic phases were combined, dried over MgSO4, filtered and evaporated to afford (R)-(2-chloro-6-(3-methylmorpholino)pyrimidin-4-yl)methyl methanesulfonate (20.14 g, 105%) which was used in the next step without further purification; 1H NMR (400 MHz, CDCl3) 1.33 (3H, d), 3.13 (3H, s), 3.27-3.34 (1H, m), 3.51-3.57 (1H, m), 3.66-3.70 (1H, m), 3.79 (1H, d), 3.99-4.03 (2H, m), 4.34 (1H, br s), 5.09 (2H, d), 6.52 (1H, s); m/z: (ESI+) MH+, 322.83.