Electric Literature of 141-86-6, In the chemical reaction process,reaction time,type of solvent,can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product.An updated downstream synthesis route of 141-86-6 as follows.
8.9 2-Amino-7-hydroxy-1,8-naphthyridine 2,6-Diaminopyridine (20?g, 0.18?mol) and (dl)-malic acid (27?g, 0.2?mol) were placed into a 500?mL three-neck round bottomed flask fitted with an addition funnel, thermometer, and mechanical stirrer. The stirred mixture was cooled in an ice-water bath and concentrated sulfuric acid (100?mL) was added drop-wise. The rate of addition was controlled to maintain an internal temperature ?45?C during the addition. Next, the addition funnel was replaced by a reflux condenser and the slurry was heated to an internal temperature of 110?C for 3?h. The solution was transferred to a 1L beaker, cooled to 0?C by an ice-water bath and was made basic (pH?=?8) by careful addition of NH4OHaq (300?mL). The crude brown solid was collected by vacuum filtration and was washed on the filter-paper with water (2?L). The solid was triturated with 1:9 (v:v) water: methanol and again collected by vacuum filtration, affording 7-amino-2-hydroxy-1,8-naphthyridine as a tan powder. Yield: 25?g (86%). 1H NMR (500?MHz, DMSO-d6): delta?=?11.91 (br s, 1H), 7.65 (d, J?=?9.5, 1H), 7.65 (d, J?=?8, 1H), 7.03 (br s, 2H), 6.34 (d, J?=?8.5, 1H), 6.12?ppm (d, J?=?9.2, 1H); 13C NMR (126?MHz; DMSO-d6): delta?=?163.8, 160.6, 150.4, 139.8, 137.4, 114.8, 105.3, 105.0?ppm; MS (ESI; CH3OH): m/z 162.0664 ([M+H]+).
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route,141-86-6, its application will become more common.
Reference:
Article; Sarkar, Mithun; Pandey, Pragati; Bera, Jitendra K.; Inorganica Chimica Acta; vol. 486; (2019); p. 518 – 528;,
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