Potassium Carbonate → (4-Oxazol-5-yl-naphthalen-1-yl)-carbamic acid tert-butyl ester

The above mixture of compounds 503A & 503B (3.37 g, 10.0 mmol; corrected for presence of compound 503A), toluene-sulfonylisocyanide (2.15 g, 11.0 mmol) and potassium carbonate (1.66 g, 12.0 mmol) in 50 mL of methanol was refluxed for 4 h. The reaction mixture was partitioned between water (200 mL) and chloroform (200 mL). After extracting the aqueous layer with chloroform (100 mL), the combined organic layers were dried over magnesium sulfate and concentrated in vacuo. The crude residue was purified by flash chromatography on silica gel eluting with a gradient of 10-40% ethyl acetate in hexane to give 1.35 g (44%) of compound 503C as a white solid. 1HNMR (400 MHz, DMSO-d6): δ 9.45 (s, 1H), 8.57 (s, 1H), 8.20 (m, 2H), 7.76 (m, 2H), 7.64 (s, 1H), 7.62 (m, 2H), 1.51 (s, 9H).

1. temperaturewas refluxed for 4 h
2. customThe reaction mixture was partitioned between water (200 mL) and chloroform (200 mL)
3. extractionAfter extracting the aqueous layer with chloroform (100 mL)
4. dry with materialthe combined organic layers were dried over magnesium sulfate
5. concentrationconcentrated in vacuo
6. customThe crude residue was purified by flash chromatography on silica gel eluting with a gradient of 10-40% ethyl acetate in hexane

ORDレコード

ord-a3244177f8ab4cb782c0ec0c8935a529

出典データセット

uspto-grants-2005_10

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US06953679B2