Diisopropylethylamine → Trifluoroacetic acid

Participants

Role	Name	HCID	Charge
Reactant	Diisopropylethylamine	HCID 81531	—
Reactant	(+-)-Tetrahydro-2-furoic acid	HCID 86079	—
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	3-(4-(2,4-difluorophenoxy)piperidin-1-yl)-N-isopropyl-5,6,7,8-tetrahydropyrido[3,4-b]pyrazin-2-amine TFA salt	HCID 131734027	—
Solvent	Dimethylacetamide	HCID 31374	—
Product	Trifluoroacetic acid	HCID 6422	260.6%
Product	(3-(4-(2,4-difluorophenoxy)piperidin-1-yl)-2-(isopropylamino)-7,8-dihydropyrido[3,4-b]pyrazin-6(5H)-yl)(tetrahydrofuran-2-yl)methanone	HCID 118159203	—

Reaction Conditions

Temperature	60 °C

Reaction Steps

To a suspension of 3-(4-(2,4-difluorophenoxyl)piperidin-1-yl)-N-isopropyl-5,6,7,8-tetrahydropyrido[3,4-b]pyrazin-2-amine TFA salt (42.8 mg, 0.070 mmol), 2-tetrahydrofuroic acid (10.1 μL, 0.105 mmol), HATU (40.0 mg, 0.105 mmol) in DMA (0.75 mL) was added DIPEA (0.037 mL, 0.211 mmol) at 23° C. The mixture was stirred at 60° C. for 30 min, cooled to 23° C., filtered, rinsed with DMSO, and purified by HPLC Method B, with the exception that a Waters XSelect® CSH C18, 5 μm, ID 4.6×50 mm was used, using an ACN gradient of 30% to 70% to give the title compound as a TFA salt (20.8 mg, 48.1%) as a hygroscopic, yellow solid. 1H NMR (400 MHz, DMSO-d6, mixture of rotamers) δ ppm 1.19 (d, J=6.3 Hz, 6H), 1.78-1.94 (m, 4H), 1.97-2.13 (m, 4H), 2.63 (t, J=5.7 Hz, 0.9H), 2.71-2.77 (m, 1.1H), 2.85-2.95 (m, 2H), 3.24-3.33 (m, 2H), 3.69-3.85 (m, 4H), 4.11 (dt, J=12.9, 6.4 Hz, 1H), 4.38-4.57 (m, 3H), 4.75 (ddd, J=14.0, 7.8, 5.7 Hz, 1H), 5.81 (br s, 1H), 6.99-7.05 (m, 1H), 7.25-7.34 (m, 2H); ESI-MS m/z [M+H]+ 502.5.

Provenance & Evidence

DOI	10.6084/m9.figshare.5104873.v1
Patent number	US09181249B2
Source dataset	uspto-grants-2015_11
ORD ID	ord-4dac36b0114c4d60b065348059095805
Source note	uspto-grants-2015_11