Oxalyl chloride → HCID 178517658, compound

Participants

Reaction Steps

In accordance with Scheme 3, the compound of formula X, 1-oxy-7H-[1,7]naphthyridin-8-one can be prepared as follows: The compound of formula IX, 7H-[1,7]naphthyridin-8-one (which can be prepared from commercially available starting product in accordance with literature Chemical & Pharmaceutical Bullentin (1985), 33(2), 626-33) was stirred for about 70 hours at room temperature in chloroform with 3-chloroperbenzoic acid to obtain the compound of formula X. To a suspension of 1-oxy-7H-[1,7]naphthyridin-8-one in dry N,N-dimethylformamide was added drop wise oxalyl chloride at 0° C. After completed addition, the mixture was allowed to warm to room temperature and stirred for about 30 minutes to obtain the compound of formula XI, 2-chloro-[1,7]naphthyridin-8-ol. To a solution of 2-chloro-[1,7]naphthyridin-8-ol in pyridine was added trifluoromethanesulfonic anhydride at about −10° C. The reaction mixture was allowed to warm to room temperature and stirred for about 1 hour to obtain the compound of formula XII, trifluoro-methanesulfonic acid 2-chloro-[1,7]naphthyridin-8-yl ester. Furthermore, the compound of formula XII and a compound of formula R2NH2, for example 2-amnio-4-methylthiazole are dissolved in dry dioxane. 4,5-Bis(diphenylphosphino)-9,9-dimethylxanthene, cesium carbonate and tri(dibenzylideneacetone)dipalladium chloroform complex are added and the reaction mixture is stirred for about 20 hrs at about 130° C. to obtain a compound of formula XIII. The desired compound of formula I can be prepared as follows: To a compound of formula XIII in dry tetrahydrofuran were added tetrakis(triphenylphosphine)palladium and a about 1.0 M solution of diethylzinc in n-hexane. The reaction mixture was heated at reflux for about 1 hour to obtain a compound of formula I.

Provenance & Evidence