D to 0 . Towards the mixture at 0 was added 1

D to 0 . Towards the mixture at 0 was added 1 mL MeOH and
D to 0 . For the mixture at 0 was added 1 mL MeOH and NaBH4 (200 mg, 5 mmol). Following stirring at 0 for five minutes, the reaction was quenched by 1 M KHSO4. The mixture was diluted with water plus the TROP-2 Protein web aqueous answer was extracted with EtOAc 3 times. The combined organic layers have been dried with MgSO4, and concentrated in vacuo. The residue was redissolved in dichloromethane and also the strong was filtered off on a small silica pad. The mixture was concentrated once more in vacuo. Purification with the residue by flash chromatography on silica gel, eluting with five 10 EtOAchexanes gave the preferred alcohol as colorless oil.J Org Chem. IL-13 Protein supplier Author manuscript; available in PMC 2014 December 06.Khumsubdee et al.PageNIH-PA Author Manuscript(2S,3R)-4-((tert-Butyldiphenylsilyl)oxy)-2-fluoro-3-methylbutan-1-ol (syn-8) The compound was ready according to the typical -fluorination procedure 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 = 48.4, 6.2, three.0 Hz, 1H), three.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 (one hundred MHz, CDCl3) 135.6 (d, J = 2.3 Hz), 133.five (d, J = three.1 Hz), 129.7 (d, J = 1.three Hz), 127.7 (s), 95.four (d, J = 170.three Hz), 64.five (d, J = six.1 Hz), 63.three (d, J = 22.2 Hz), 37.1 (d, J = 18.9 Hz), 26.9 (s), 19.three (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 (big 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.Web page(2R,3R)-4-((tert-Butyldiphenylsilyl)oxy)-2-fluoro-3-methylbutan-1-ol (anti-8) The compound was prepared based on the standard -fluorination process catalysed by (R)-5-benzyl-2,2,three,-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), four.72 (dtd, J = 48.8, 6.four, three.1 Hz, 1H), three.97 three.75 (m, 2H), 3.67 3.64 (m, 2H), two.28 (br, 1H), 2.11 2.00 (m, 1H), 1.12 (s, 9H), 0.99 (dd, J = 7.0, 0.8 Hz, 3H); 13C NMR (one hundred MHz, CDCl3) 135.six (d, J = 4.five Hz), 133.three (d, J = eight.2 Hz), 129.8 (s), 127.8 (d, J = 1.6 Hz), 95.4 (d, J = 171.0 Hz), 65.2 (d, J = 6.0 Hz), 63.7 (d, J = 22.six Hz), 37.four (d, J = 19.six Hz), 26.9 (s), 11.7 (d, J = 5.8 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 (key diastereomer). Relative stereochemistry determination of 8: due to the fact both catalyst and reaction situation are identical to what has been reported, and the reaction is catalyst controlled; the stereochemistry was assigned based on MacMillan’s fluorinated produ.