Diisopropylethylamine → (S)-tert-Butyl 3-(((9H-fluoren-9-yl)methoxy)carbonylamino)-4-((benzo[b]thiophen-3-ylmethyl)((S)-1,1-diethoxypropan-2-yl)amino)-4-oxobutanoate

Participants

Role	Name	HCID	Charge
Reactant	Diisopropylethylamine	HCID 81531	—
Reactant	Fmoc-L-Asp(OtBu)-OH	HCID 2724635	—
Reactant	Methanaminium, N-((dimethylamino)(3H-1,2,3-triazolo(4,5-b)pyridin-3-yloxy)methylene)-N-methyl-, hexafluorophosphate(1-) (1:1)	HCID 9886157	—
Reactant	(S)-N-(benzo[b]thiophen-3-ylmethyl)-1,1-diethoxypropan-2-amine	HCID 67088371	—
Solvent	Water	HCID 962	—
Solvent	Dimethylformamide	HCID 6228	—
Solvent	Ethyl Acetate	HCID 8857	—
Product	(S)-tert-Butyl 3-(((9H-fluoren-9-yl)methoxy)carbonylamino)-4-((benzo[b]thiophen-3-ylmethyl)((S)-1,1-diethoxypropan-2-yl)amino)-4-oxobutanoate	HCID 67075020	66%

Reaction Steps

According to the procedure described in the synthesis method of Compound III-1, (S)—N-(benzo[b]thiophen-3-ylmethyl)-1,1-diethoxypropan-2-amine (Compound IX-6) 13.2 g (45 mmol) and Fmoc-Asp(tBu)-OH 24.2 g (58.8 mmol) were dissolved in DMF (200 ml). HATU (25.6 g, 67.5 mmol) and DIEA (8.7 g, 67.5 mmol) were added at room temperature. The mixture was stirred overnight at room temperature. The mixture was poured into water (800 ml). The solution was extracted with EA (300 ml×3). The combined extracts were dried over Na2SO4 and then filtered. The solvent was removed in vacuo. The residue was purified by column chromatography on silica gel with PE:EA=30:1 to 5:1 to give the title compound 20.4 g, (yield 66%).

Provenance & Evidence

DOI	10.6084/m9.figshare.5104873.v1
Patent number	US09193734B2
Source dataset	uspto-grants-2015_11
ORD ID	ord-d248dd02de104849a78f8383223db02e
Source note	uspto-grants-2015_11