1,4-Dioxane → 2-amino-4-ethyl-5-(2-methyl-2H-pyrazol-3-yl)-benzoic acid methyl ester

Participants

Role	Name	HCID	Charge
Reactant	1,4-Dioxane	HCID 31275	—
Reactant	1-Methyl-5-(tributylstannyl)-1H-pyrazole	HCID 21867455	—
Reactant	Methyl 2-amino-4-ethyl-5-iodobenzoate	HCID 53424411	—
Catalyst	Bis(cyclopenta-1,4-dien-1-yl(diphenyl)phosphane);dichloropalladium;iron(2+)	HCID 178418228	—
Solvent	Ethyl Acetate	HCID 8857	—
Product	2-amino-4-ethyl-5-(2-methyl-2H-pyrazol-3-yl)-benzoic acid methyl ester	HCID 59164471	68.3%

Reaction Conditions

Temperature	100 °C

Reaction Steps

2-Amino-5-iodo-4-ethyl-benzoic acid methyl ester (280 mg, 0.92 mmol) and 1-methyl-5-tributylstannanyl-1H-pyrazole (409 mg, 1.2 equiv) were weighed in air and added to a flame-dried flask. [1,1′-bis(diphenylphosphino)-ferrocene]dichloropalladium (75 mg, 0.1 equiv) was added and the flask was closed by a septum. Dioxane (1 mL) was added and the mixture was stirred at 100° C. for 18 h (TLC control). The mixture was dissolved with EtOAc, filtered and evaporated to dryness. The crude product was purified by flash chromatography (hexanes to EtOAc/hexanes (4:6)) to yield 2-amino-4-ethyl-5-(2-methyl-2H-pyrazol-3-yl)-benzoic acid methyl ester (163 mg, 68% yield) as a yellow solid. ESI-MS: m/z 260.3 [M+H]+, rt 6.37 min.

Provenance & Evidence

DOI	10.6084/m9.figshare.5104873.v1
Patent number	US08012988B2
Source dataset	uspto-grants-2011_09
ORD ID	ord-139aa7e9fc524e31ab2a94840ad9736e
Source note	uspto-grants-2011_09