3-Nitro-4-hydroxy-6-methyl-2H-pyran-2-one synthesis

Yield:668-43-9 79%

Reaction Conditions:

with sulfuric acid;nitric acid at 0; for 0.666667 h;

Steps:

3-Amino-4-hydroxy-6-methyl-2H-pyran-2-one (23)

To a cold (0 °C) solution of 4-hydroxy-6-methyl-2H-pyran-2-one (79.3 mmol) in H₂SO₄ (25 mL) was added dropwise a mixture of H₂SO₄ (4.23 mL) and HNO₃ (119 mmol) over 10 min. After stirring for 30 min, the mixture was poured into ice-water, and the precipitate was collected by filtration, washed with cold H₂O (3×) and dried under vacuum to give 4-hydroxy-6-methyl-3-nitro-2H-pyran-2-one as a white solid; yield: 10.7 g (79%); mp 163-166 °C (Lit. ¹⁸ 165 °C). IR (solid form): 1748, 1639, 1530, 1215, 1194, 1086, 996, 827, 783 cm^-1. ¹H NMR (400 MHz, CDCl₃): δ = 11.21 (br s, 1 H, OH), 6.14 (s, 1H, =CH), 2.37 (s, 3 H, CH3). ¹³C NMR (100 MHz, DMSO-d₆): δ = 166.4, 165.4, 156.6, 119.5, 100.7, 19.8.MS (ESI, MeOH, negative ion mode): m/z = 170.4 ([M - H]^-).

References:

Prior, Allan M.;Gunaratna, Medha J.;Kikuchi, Daisuke;Desper, John;Kim, Yunjeong;Chang, Kyeong-Ok;Maezawa, Izumi;Jin, Lee-Way;Hua, Duy H. [Synthesis,2014,vol. 46,# 16,art. no. SS-2014-M0160-OP,p. 2179 - 2190]