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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 521341Generated: October 30, 2026

Formamide → HCID 178461168, compound

https://huagongshe.com/reaction/521341

Reaction equation

Participants

RoleNameHCIDCharge
ReactantFormamideHCID 713—
ReactantAmmonium formateHCID 2723923—
ReactantEthyl (5R)-2-amino-5-methyl-1-cyclopentene-1-carboxylateHCID 59671147—
ProductHCID 178461168HCID 17846116865%

Reaction Conditions

Temperature150 °C

Reaction Steps

A solution containing (R)-ethyl 2-amino-5-methylcyclopent-1-enecarboxylate (161.6 g, 955 mmol) and ammonium formate (90.3 g, 1433 mmol) in formamide (303.5 mL, 7640 mmol) was heated to an internal temperature of 150° C. and stirred for 17 hours. The reaction mixture was cooled, and transferred to a 2 L single nextracted flask. Excess formamidine was then removed by high vacuum distillation. Once formamidine stopped coming over, the remaining oil in the still pot was dissolved in DCM and washed with brine (3×200 mL). The combined aqueous washes were extracted with DCM. The combined organic extracts were dried (Na2SO4), filtered, and concentrated. The resulting oil was dissolved in minimal DCM, and this solution was added using a separatory funnel to a stirred solution of ether (about 5 volumes of ether vs. DCM solution), causing some precipitate to form. This precipitate was removed by filtration through a medium frit funnel which was rinsed with ether and disposed. The filtrate was concentrated, the trituration from ether repeated two more times and then dried on high vacuum line to give (R)-5-methyl-6,7-dihydro-5H-cyclopenta[d]pyrimidin-4-ol (93.2 g, 65.0% yield) as a pasty solid. LC/MS (APCI−) m/z 149.2.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS09328091B2
Source datasetuspto-grants-2016_05
ORD IDord-a5a3e4a158cd41d1bd5d008e6e7da5bb
Source noteuspto-grants-2016_05