Ethyl orthoformate → HCID 90402410, compound

Participants

Reaction Steps

(Z)-2-cyclopropyl-2-((R)-1,1-dimethylethylsulfinamido)-N′-hydroxypropanimidamide (321 mg, 1.30 mmol) in triethoxymethane (2.0 ml, 12 mmol) was treated with AcOH (2 ml) at rt. The reaction was allowed to stir at rt for 16 h. LCMS showed a major peak with the expected M+H. The reaction was concentrated to dryness azeotroping with toluene 2×. The resulting yellow oil was purified on silica gel (Biotage, EtOAc/hexanes gradient (Rf ˜0.2 in 70% EtOAc/Hex, visualized with permanganate stain), to give the expected product (first eluting diastereomer, 120 mg, 0.466 mmol, 36% yield) consistent by LCMS and NMR. LC-MS retention time: 1.21 min; m/z M+H: 258. LC data was recorded on a Shimadzu LC-10AS liquid chromatograph equipped with a Phenomenex-Luna 3u C18 2.0×30 mm column using a SPD-10AV UV-Vis detector at a detector wave length of 220 nM. The elution conditions employed a flow rate of 1 mL/min, a gradient of 100% solvent A/0% solvent B to 0% solvent A/100% solvent B, a gradient time of 2 min, a hold time of 1 min, and an analysis time of 3 min where solvent A was 10% acetonitrile/90% H2O/0.1% trifluoroacetic acid and solvent B was 10% H2O/90% acetonitrile/0.1% trifluoroacetic acid. MS data was determined using a Micromass Platform for LC in electrospray mode. 1H NMR (500 MHz, DMSO-d6) δ 9.53 (s, 1H), 5.29 (s, 1H), 1.53-1.49 (m, 1H), 1.47 (s, 3H), 1.10 (s, 9H), 0.49-0.40 (m, 4H).

Provenance & Evidence