Potassium Carbonate → methyl 4-(1,4-dimethyl-1H-pyrazol-5-yl)-5-ethyl-2-thiophenecarboxylate

Participants

Role	Name	HCID	Charge
Reactant	Potassium Carbonate	HCID 11430	—
Reactant	Trimethylboroxine	HCID 574072	—
Reactant	methyl 4-(4-bromo-1-methyl-1H-pyrazol-5-yl)-5-ethyl-2-thiophenecarboxylate	HCID 57826735	—
Catalyst	Bis(cyclopenta-1,4-dien-1-yl(diphenyl)phosphane);dichloropalladium;iron(2+)	HCID 178418228	—
Solvent	Dimethylformamide	HCID 6228	—
Product	methyl 4-(1,4-dimethyl-1H-pyrazol-5-yl)-5-ethyl-2-thiophenecarboxylate	HCID 57826857	96%

Reaction Steps

A solution of methyl 4-(4-bromo-1-methyl-1H-pyrazol-5-yl)-5-ethyl-2-thiophenecarboxylate (635 mg, 1.93 mmol), potassium carbonate (1.33 g, 9.64 mmol), PdCl2(dppf) (141 mg, 0.19 mmol) and trimethylboroxine (0.54 ml, 3.86 mmol) in N,N-dimethylformamide (3 ml) was stirred at 110° C. in a sealed tube for 2 h. This reaction mixture was concentrated and partitioned between H2O-DCM. The aqueous phase was washed several times with DCM and the combined organic fractions were dried over Na2SO4, concentrated and purified via column chromatography (10-50% EtOAc in hexanes) affording the title compound (488 mg, 96%) as a yellow oil: LCMS (ES) m/e 265 (M+H)+.

Provenance & Evidence

DOI	10.6084/m9.figshare.5104873.v1
Patent number	US08273782B2
Source dataset	uspto-grants-2012_09
ORD ID	ord-6939e6408f464740b9fe5645a39f7121
Source note	uspto-grants-2012_09