D to 0 . To the mixture at 0 was added 1 mL MeOH and
D to 0 . To the mixture at 0 was added 1 mL MeOH and NaBH4 (200 mg, 5 mmol). Following stirring at 0 for 5 minutes, the reaction was quenched by 1 M KHSO4. The mixture was diluted with water and the aqueous resolution was extracted with EtOAc three instances. The combined organic layers have been dried with MgSO4, and concentrated in vacuo. The residue was redissolved in dichloromethane and also the solid was filtered off on a modest silica pad. The mixture was concentrated once more in vacuo. Purification from the residue by flash chromatography on silica gel, eluting with 5 ten EtOAchexanes gave the desired alcohol as colorless oil.J Org Chem. Author manuscript; obtainable in PMC 2014 December 06.Khumsubdee et al.PageNIH-PA Author Manuscript(2S,3R)-4-((LacI Protein manufacturer tert-Butyldiphenylsilyl)oxy)-2-fluoro-3-methylbutan-1-ol (syn-8) The compound was prepared according to the common -fluorination process catalysed by (S)-5-benzyl-2,2,three,-trimethylimidazolidin-4-one dichloroacetic acid salt. Purification by flash chromatography afforded syn-8 as a colorless oil (162 mg, 90 isolated yield). 1H NMR (400 MHz, CDCl3) 7.72 7.69 (m, 4H), 7.51 7.39 (m, 6H), four.66 (dtd, J = 48.four, 6.2, three.0 Hz, 1H), 3.96 3.68 (m, 4H), 2.22 two.01 (m, 2H), 1.11 (s, 9H), 1.04 (d, J = 7.0 Hz, 3H); 13C NMR (100 MHz, CDCl3) 135.six (d, J = two.three Hz), 133.five (d, J = three.1 Hz), 129.7 (d, J = 1.3 Hz), 127.7 (s), 95.4 (d, J = 170.3 Hz), 64.five (d, J = six.1 Hz), 63.3 (d, J = 22.2 Hz), 37.1 (d, J = 18.9 Hz), 26.9 (s), 19.3 (s), 13.0 (d, J = six.eight Hz); 19F NMR (282 MHz, CDCl3) -194.48 (dtd, J = 40.0, 25.three, 14.five Hz). IR (CH2Cl2) n (cm-1) 3364, 3071, 2928, 2855, 2361, 1470, 1427, 1393, 1362, 1111, 1049. HRMS (ESI, TOF): mz = 361.2021, calcd For C21H30FO2Si [MH] 361.1999. The diastereoselectivity was 19F NMR and confirmed by 22:1.0 determined by Chiral HPLC (Chiralcel OD, HexiPrOH 99:1, 1 mLmin, 25 ), tr 16.05 min (major MMP-1 Protein supplier diastereomer), tr 23.68 min (minor diastereomer).NIH-PA Author Manuscript NIH-PA Author ManuscriptJ Org Chem. Author manuscript; accessible in PMC 2014 December 06.Khumsubdee et al.Page(2R,3R)-4-((tert-Butyldiphenylsilyl)oxy)-2-fluoro-3-methylbutan-1-ol (anti-8) The compound was ready in accordance with the common -fluorination process catalysed by (R)-5-benzyl-2,two,3,-trimethylimidazolidin-4-one dichloroacetic acid salt. Purification by flash chromatography afforded anti-8 as a colorless oil (153 mg, 85 isolated yield). 1H NMR (400 MHz, CDCl3) 7.74 7.69 (m, 4H), 7.51 7.41 (m, 6H), 4.72 (dtd, J = 48.8, six.4, 3.1 Hz, 1H), three.97 three.75 (m, 2H), three.67 3.64 (m, 2H), two.28 (br, 1H), two.11 2.00 (m, 1H), 1.12 (s, 9H), 0.99 (dd, J = 7.0, 0.eight Hz, 3H); 13C NMR (one hundred MHz, CDCl3) 135.6 (d, J = four.five Hz), 133.three (d, J = eight.two Hz), 129.eight (s), 127.eight (d, J = 1.6 Hz), 95.4 (d, J = 171.0 Hz), 65.two (d, J = 6.0 Hz), 63.7 (d, J = 22.6 Hz), 37.four (d, J = 19.6 Hz), 26.9 (s), 11.7 (d, J = five.8 Hz); 19F NMR (282 MHz, CDCl3) -198.46 -198.93 (m). IR (CH2Cl2) n (cm-1) 3356, 3071, 2932, 2859, 2361, 1470, 1427, 1389, 1362, 1111, 1034. HRMS (ESI, TOF): mz = 361.2035, calcd For C21H30FO2Si [MH] 361.1999. The diastereoselectivity was 1.0:58, determined by 19F NMR and confirmed by Chiral HPLC (Chiralcel OD, HexiPrOH 99:1, 1 mLmin, 25 ), tr 16.05 min (minor diastereomer), tr 23.68 min (main diastereomer). Relative stereochemistry determination of eight: due to the fact each catalyst and reaction situation are identical to what has been reported, plus the reaction is catalyst controlled; the stereochemistry was assigned in line with MacMillan’s fluorinated produ.