Acetic Acid → tert-butyl(2S)-2-{[2-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)ethyl]amino}-3,3-dimethylbutanoate

HRID 1174129Notes

Reaction equation

[O:1]=[C:2]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[C:4](=[O:11])[N:3]1[CH2:12][CH:13]=O.Cl.[C:16]([O:20][C:21](=[O:28])[C@H:22]([C:24]([CH3:27])([CH3:26])[CH3:25])[NH2:23])([CH3:19])([CH3:18])[CH3:17].C([BH3-])#N.[Na+].C(O)(=O)C>CO.C(Cl)(Cl)Cl.C(OCC)(=O)C>[O:11]=[C:4]1[C:5]2[C:10](=[CH:9][CH:8]=[CH:7][CH:6]=2)[C:2](=[O:1])[N:3]1[CH2:12][CH2:13][NH:23][C@@H:22]([C:24]([CH3:27])([CH3:26])[CH3:25])[C:21]([O:20][C:16]([CH3:18])([CH3:17])[CH3:19])=[O:28]

Participants

Conditions

Temperature: 25 °C

Procedure

A solution of the product of Example 3E (9.34 g, 49.4 mmol) in methanol (33 mL) was treated with L-tert-leucine tert-butyl ester hydrochloride (10 g, 44.9 mmol), sodium cyanoborohydride (5.6 g, 89.8 mmol), and acetic acid (1.5 ml, 26.2 mmol), stirred at 25° C. for 4 hours, and partitioned between chloroform and saturated NaHCO3. The organic phase was washed with brine, dried over MgSO4, filtered and concentrated. The residue was chromatographed on silica gel, eluting with first with 66% chloroform in hexanes and then with 33% ethyl acetate in chloroform to give the title compound (10.5 g, 59% yield).

Workup

custompartitioned between chloroform and saturated NaHCO3
washThe organic phase was washed with brine
dry with materialdried over MgSO4
filtrationfiltered
concentrationconcentrated
customThe residue was chromatographed on silica gel
washeluting with first with 66% chloroform in hexanes

Sources & evidence

ORD record: ord-00a8a93ce66e464f9983543c2997f649
Source dataset: uspto-grants-2010_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07834043B2

Reaction notes

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