A one-pot, two-step microwave-assisted synthesis of highly functionalized benzoxazoles using solid-supported reagents (SSRs)

Tetrahedron Letters

Volumn 49, Issue 29-30, 2008, Pages 4464-4466

  Radi, Marco ^a   Saletti, Sara ^a   Botta, Maurizio ^a  

^a UNIVERSITY OF SIENA   (Italy)

Author keywords

Benzoxazoles; Combinatorial chemisrty; Microwave; Solid supported reagents

Indexed keywords

ALCOHOL; AMINE; BENZOXAZOLE DERIVATIVE; ESTER; PHENOL;

ACYLATION; ARTICLE; DRUG SYNTHESIS; MICROWAVE RADIATION;

EID: 44749087580     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2008.05.059     Document Type: Article

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30. 2 (3 mL) for 10 min. The required aminophenols were added, the resulting mixture stirred for additional 10 min, and finally evaporated in parallel (14 per time). The neat crude mixtures were irradiated into the microwave at 300 W for 10 min each. The resins were then swelled with toluene (3 mL), PTSA-polymer bound (8 equiv) was added and the resulting mixtures were irradiated into the microwave for 10 min at 180 °C. The combined solid supports were removed by parallel filtration then evaporation and trituration with hexane gave the desired benzoxazoles 9 in high purity.
31. 13 and their loading was calculated by cleavage of the corresponding benzylamides: considering the theoretical loading of the SSR equal to that of the Merrifield resin (1.25 mmol/g), reaction with 1.25 mmol of benzylamine gave an amount of benzylamide equal to the real loading (see Table 1).