Diisopropylethylamine → (R)-tert-butyl 3,3-dimethyl-1-(methylamino)-1-oxobutan-2-ylcarbamate

Participants

Role	Name	HCID	Charge
Reactant	Diisopropylethylamine	HCID 81531	—
Reactant	O-(Benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate	HCID 2733207	—
Reactant	Methylamine hydrochloride	HCID 6364545	—
Reactant	(2R)-2-{[(tert-butoxy)carbonyl]amino}-3,3-dimethylbutanoic acid	HCID 7005057	—
Solvent	Acetonitrile	HCID 6342	—
Product	(R)-tert-butyl 3,3-dimethyl-1-(methylamino)-1-oxobutan-2-ylcarbamate	HCID 57635611	77.7%

Reaction Steps

To a cold solution of (R)-2-(tert-butoxycarbonylamino)-3,3-dimethylbutanoic acid (0.50 g, 2.16 mmol) in acetonitrile (8 mL) was added methylamine hydrochloride (0.48 g, 7.13 mmol), followed by DIEA (1.67 g, 12.9 mmol). The resulting mixture was stirred for 20 min and TBTU (0.76 g, 2.37 mmol) was added and the stiffing continued overnight. The mixture was concentrated, diluted with EtOAc (30 mL) and washed successively with aqueous 5% KHSO4, saturated NaHCO3 solution and brine, dried over anhydrous Na2SO4, filtered and concentrated to provide Intermediate 30A (0.41 g, 77%).

Provenance & Evidence

DOI	10.6084/m9.figshare.5104873.v1
Patent number	US08859538B2
Source dataset	uspto-grants-2014_10
ORD ID	ord-b49b5aa94b6f46d9979b7d86e75972db
Source note	uspto-grants-2014_10