ChemicalBook CAS DataBase List 2-Methyl-4H-3,1-benzoxazin-4-one

2-Methyl-4H-3,1-benzoxazin-4-one synthesis

13synthesis methods

Product Name:2-Methyl-4H-3,1-benzoxazin-4-one
CAS Number:525-76-8
Molecular formula:C9H7NO2
Molecular Weight:161.16

In 250 mL of RBF took (0.01 mole or 1.37 gm) anthranilic acid (2-amino benzoic acid) to that added 15 mL of acetic anhydride (excess) with porcelain chips. Reflux the solution at 35-40 ℃ for 50-55 min on heating mantle. TLC was done using EA: n-hexane (1:1) solvent system. Then removed the excess solvent (acetic anhydride) at low pressure using rotatory evaporator, To the remaining solid, added petroleum ether (40-60) to extract the 2-methyl-4H-3,1-benzoxazin-4-one. Repeated petroleum ether step to extract the entire product. After drying of petroleum-ether, the crystals of 2-methyl-4H-3, 1-benzoxazin-4-one was obtained and then it was recrystallized with ethanol8. M.P 80-82℃, Yield 79 %.
2-METHYL-3,1-BENZOXAZA-4-ONE

108-24-7
5 suppliers
$14.00/250ML

118-92-3
4 suppliers
$21.60/25g

525-76-8
141 suppliers
$51.79/10g

Yield:525-76-8 100%

Reaction Conditions:

at 130; for 3 h;

Steps:

14
Synthesis of 2-methyl-4H-3,1-benzoxazin-4-one. Anthranilic acid (1.8 g, 13.1 mmol) and acetic anhydride (20 ml_, excess) were mixed and refluxed at 130 ⁰C for 3 hours. The excess acetic anhydride was removed under high vacuum to afford 2-methyl-4H-3,1-benzoxazin-4-one (2.1 g, 100%) as an oily product: TLC (ethyl acetate / hexane, 1/2 v/v) R_f = 0.3.

References:

XENON PHARMACEUTICALS INC. WO2008/94909, 2008, A2 Location in patent:Page/Page column 99

201230-82-2 Synthesis