Formic Acid → (1S,3S)-3-[(tert-Butoxycarbonyl)amino]cyclopentyl formate

Reaction equation

N(C(OCC)=O)=N[C:3](OCC)=[O:4].[CH3:13][C:14]([O:17][C:18](=[O:26])[NH:19][C@H:20]1[CH2:24][CH2:23][C@@H:22]([OH:25])[CH2:21]1)([CH3:16])[CH3:15].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C(O)=O>>[CH3:16][C:14]([O:17][C:18](=[O:26])[NH:19][C@H:20]1[CH2:24][CH2:23][C@H:22]([O:25][CH:3]=[O:4])[CH2:21]1)([CH3:13])[CH3:15]

Participants

Reactant 4

HCID 284Formic Acid

HCID 11776Triphenylphosphine

HCID 220568ethyl N-ethoxycarbonyliminocarbamate

HCID 216370811,1-Dimethylethyl N-((1S,3R)-3-hydroxycyclopentyl)carbamate

Product 1

HCID 86754023(1S,3S)-3-[(tert-Butoxycarbonyl)amino]cyclopentyl formateYield 50.1%

Procedure

Diethyl azodicarboxylate (0.164 ml, 1.23 mmol) was added dropwise to a stirred solution of (1S-cis)-(3-hydroxycyclopentyl)carbamic acid 1,1-dimethylethyl ester (0.124 g, 0.61 mmol), triphenylphosphine (0.323 g, 1.23 mmol) and formic acid (0.046 ml, 1.23 mmol) and the solution was stirred at room temperature for 2 h The solution was then concentrated and purified by column chromatography on flash silica eluting with 10-30% ethyl acetate in cyclohexane to give the title compound (0.07 g) as white needles from diisopropyl ether m p.84°-85° C., [α]D -12.7° (CHCl3 c=0.55%).