Synthesis of N‐Substituted‐6‐alkoxypteridin‐4‐amine

Abstract

A novel seven‐step methodology for the synthesis of N‐substituted‐6‐alkoxypteridin‐4‐amine has been developed with the total yields of 35.4–41%. Twenty new compounds were synthesized by heterocyclization of easily prepared 3‐amino‐6‐bromopyrazine‐2‐carboxamide, subsequent alkoxylation, chlorination, and nucleophilic substitution. Their structures were confirmed by 1H‐NMR, 13C‐NMR, ESI‐MS, and elemental analysis. The structure of N‐(3‐chloro‐4‐fluorophenyl)‐6‐ethoxypteridin‐4‐amine was further determined by X‐ray crystallographic analysis. It was found that different chlorinating reagents gave different products. The possible chlorination mechanism was discussed.

Nickel-Catalyzed Synthesis of Quinazolinone Derivatives in Polyethylene Glycol 200

“…269 ～ 271 ℃ (lit. [20] 268 ～ 270 ℃ ); 1 H NMR (400 MHz, DMSO-d 6 ) δ: 13.01 (s, 1H), 9.14 (s, 1H), 8.41 (s, 1H); 13 C NMR (100 MHz, DMSO-d 6 ) δ: 159.82, 154.80, 153.21, 150.16, 138.12, 135.14…”

Silver-Catalyzed Chlorocyclization for the Synthesis of 3-Chloro-2H-chromenes

“…Chlorine has been widely found in pesticides, pharmaceuticals, and natural products. − It plays an important role in organic synthesis as it enables molecules with the possibility of further functionalization, especially in the field of cross-coupling. − Therefore, finding an efficient chlorination process has been an interesting area for organic chemists. Traditional chlorination usually employs sulfuryl chloride, chlorine, phosphorous oxychloride, − or hydrogen chloride , as the chlorination regents under heat or light. Because of the drawbacks of their low stability and high toxicity, there is an urgent need to develop new protocols for the chlorination process.…”