Synthesis
GENERAL METHOD: Triethyl orthoformate (1.1 mmol) and o-amino-p-toluol (1 mmol) were mixed and p-toluenesulfonic acid (TSA, 1 mol%) was added as a catalyst. The reaction mixture was stirred at 80-90 °C for an appropriate time depending on the course of the reaction (cf. Table 4). After completion of the reaction (monitored by TLC), the reaction mixture was diluted with chloroform (10 mL) and the catalyst was removed by filtration. The final product 5-methylbenzazole was purified by column chromatography.
References
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[2] Combinatorial Chemistry and High Throughput Screening, 2013, vol. 16, # 8, p. 618 - 627
[3] Chemical Communications, 2014, vol. 50, # 73, p. 10661 - 10664
[4] Monatshefte fur Chemie, 2007, vol. 138, # 7, p. 663 - 667
[5] Comptes Rendus Chimie, 2013, vol. 16, # 11, p. 1029 - 1034
