Isobutyryl chloride → [(3S,6S,7R,8S)-3-[bis(tert-butoxycarbonyl)amino]-6-methyl-8-(1-naphthylmethyl)-4-oxo-1,5-dioxonan-7-yl]2-methylpropanoate

HRID 58960Notes

Reaction equation

HRID 58960 reaction equation
[C:1]([O:5][C:6]([N:8]([C@H:16]1[CH2:24][O:23][CH2:22][C@H:21]([CH2:25][C:26]2[C:35]3[C:30](=[CH:31][CH:32]=[CH:33][CH:34]=3)[CH:29]=[CH:28][CH:27]=2)[C@@H:20]([OH:36])[C@H:19]([CH3:37])[O:18][C:17]1=[O:38])[C:9](=[O:15])[O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:7])([CH3:4])([CH3:3])[CH3:2].[C:39](Cl)(=[O:43])[CH:40]([CH3:42])[CH3:41]>CN(C1C=CN=CC=1)C.C(Cl)Cl>[C:11]([O:10][C:9]([N:8]([C:6]([O:5][C:1]([CH3:2])([CH3:3])[CH3:4])=[O:7])[C@@H:16]1[C:17](=[O:38])[O:18][C@@H:19]([CH3:37])[C@H:20]([O:36][C:39](=[O:43])[CH:40]([CH3:42])[CH3:41])[C@@H:21]([CH2:25][C:26]2[C:35]3[C:30](=[CH:31][CH:32]=[CH:33][CH:34]=3)[CH:29]=[CH:28][CH:27]=2)[CH2:22][O:23][CH2:24]1)=[O:15])([CH3:13])([CH3:14])[CH3:12]

Participants

5

Procedure

To a solution of tert-butyl N-tert-butoxycarbonyl-N-[(3S,7S,8R,9S)-8-hydroxy-9-methyl-7-(1-naphthylmethyl)-2-oxo-1,5-dioxonan-3-yl]carbamate (290 mg, 0.548 mmol) and DMAP (201 mg, 1.64 mmol) in CH2Cl2 (2.7 mL) was added isobutyryl chloride (86 μL, 0.821 mmol) slowly to the flask and the resulting solution was stirred at room temperature for 20 h. The reaction mixture was dissolved in CH2Cl2 (4 mL), treated with Celite®, the solvent evaporated, and the adsorbed crude material purified by flash chromatography (SiO2, 0→15% EtOAc/hexanes) to provide [(3S,6S,7R,8S)-3-[bis(tert-butoxycarbonyl)amino]-6-methyl-8-(1-naphthylmethyl)-4-oxo-1,5-dioxonan-7-yl]2-methylpropanoate (270 mg, 82%) as a white powder: mp 130-132° C.; 1H NMR (400 MHz, CDCl3) δ 8.01-7.93 (m, 1H), 7.84 (dd, J=8.0, 1.5 Hz, 1H), 7.72 (d, J=8.1 Hz, 1H), 7.54-7.41 (m, 2H), 7.37 (dd, J=8.2, 7.0 Hz, 1H), 7.28 (dd, J=7.0, 1.3 Hz, 1H), 5.20 (dd, J=8.7, 5.7 Hz, 1H), 5.11 (app t, J=9.3 Hz, 1H), 5.08-4.97 (m, 1H), 4.06 (dd, J=11.8, 5.7 Hz, 1H), 3.86 (dd, J=11.9, 8.7 Hz, 1H), 3.66 (d, J=11.0 Hz, 1H), 3.50 (dd, J=10.8, 6.4 Hz, 1H), 3.23 (dd, J=14.0, 3.1 Hz, 1H), 2.74-2.55 (m, 2H), 2.37-2.20 (m, 1H), 1.42 (s, 18H), 1.37 (d, J=6.2 Hz, 3H), 1.26 (app dd, J=7.0, 4.4 Hz, 6H); ESIMS m/z 622 ([M+Na]+).

Workup

  1. additiontreated with Celite®
  2. customthe solvent evaporated
  3. customthe adsorbed crude material purified by flash chromatography (SiO2, 0→15% EtOAc/hexanes)

Sources & evidence

ORD record
ord-8244359ac43b40219e34a9e8d21e5cdd
Source dataset
uspto-grants-2016_09
Patent number
US09439422B2

Reaction notes

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