ChemicalBook CAS DataBase List 6-nitrocoumarin

6-nitrocoumarin synthesis

8synthesis methods

Product Name:6-nitrocoumarin
CAS Number:2725-81-7
Molecular formula:C9H5NO4
Molecular Weight:191.14

91-64-5

2725-81-7

The method was carried out with reference to the literature (Roy et al., 2011). In a 250 mL three-necked flask equipped with a condenser tube, thermometer and dropping funnel, coumarin (10 g, 68.5 mmol) and 50 mL of concentrated sulfuric acid (0.935 mol) were added. After cooling the reaction system to -10 °C, a mixture consisting of concentrated sulfuric acid (15 mL, 0.28 mol) and fuming nitric acid (5 mL, 0.12 mol) was added slowly and dropwise over a period of 1 hour, during which the reaction temperature was kept below -5 °C. Upon completion of the reaction, the mixture was decanted into ice water, the precipitate was collected by filtration and recrystallized from acetic acid. A white solid 11.26 g of 6-nitro-2H-benzopyran-2-one was obtained in 86% yield with a melting point of 191-192.5 °C (literature value 188-190 °C). The structure of the product was confirmed by 1H NMR and 13C NMR: 1H NMR (400.13 MHz, CDCl3) δ 6.60 (d, J = 9.5 Hz, 1H), 7.48 (d, J = 9.0 Hz, 1H), 7.83 (d, J = 9.5 Hz, 1H), 8.42 (dd, J = 9.0 Hz, 2.5 Hz, 1H). 8.46 (d, J = 2.5 Hz, 1H); 13C NMR (100.62 MHz, CDCl3) δ 118.1, 118.8, 118.8, 123.7, 126.6, 142.2, 144.0, 157.5, 158.8.

91-64-5 Synthesis

91-64-5
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2725-81-7
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Yield:2725-81-7 98%

Reaction Conditions:

Stage #1:coumarin with sulfuric acid at 4; for 0.166667 h;
Stage #2: with guanidine nitrate

Steps:

Synthesis of 6-nitro-coumarin a
6-nitro-coumarin a was synthesied accroding to the lit (Wang et al. 2015). The concentrated sulphuric acid (29 mL) was added to coumarin (0.1 mol, 14.6 g) at 4 °C, and the mixture was stirred for 10 min. Then guanidine nitrate (0.1 mol, 12.2 g) was added slowly. The reaction was monitored by TLC. After completion of the reaction, the resulting mixture was slowly poured into crushed ice and the resulting solid was separated by filtration and washed successively with water. The product was dried to get white compound a in yield of 98%; HPLC>98.0%

References:

Ding, Yin-hao;Dong, Jing-jing;Feng, Bai-cheng;Hao, Shuang-hong;Jin, Yan;Wei, Yan [Natural Product Research,2020] Location in patent:supporting information

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