Microwave-assisted N-Boc deprotection under mild basic conditions using K3PO4·H2O in MeOH

Tetrahedron Letters

Volumn 50, Issue 9, 2009, Pages 1071-1074

  Dandepally, Srinivasa Reddy ^a   Williams, Alfred L ^a  

^a NORTH CAROLINA CENTRAL UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CARBONYL DERIVATIVE; METHANOL; POTASSIUM DERIVATIVE;

ALKALINITY; ARTICLE; DEPROTECTION REACTION; MICROWAVE IRRADIATION; QUANTUM YIELD; REACTION ANALYSIS; REACTION TIME;

EID: 58149512802     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2008.12.074     Document Type: Article

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25. Dandepally, S. R.; Williams, A. L. submitted for publication.
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27. ™ a single-mode automated microwave reactor was used for all the microwave irradiation assisted reactions.Conditions for MeOH solvent: Set temperature 120 °C; Ramp time 2.5 min (temperature usually reached by 1.5 min); observed pressure 100 psi (maximum pressure 250 psi); initial observed power 100 W, after ramp 50 W (maximum power 300 W); stirring on; cooling on.
28. 2O (16 mg, 0.069 mmol) and heated at reflux for 30 min. Reaction was worked up as described above to give the product 2b (62 mg, 95%) as a white solid.
29. 2O (2 equiv) in MeOH with both microwave irradiation (30 min) and conventional heating (24 h) failed to give 3-(piperazin-1-yl)phenol.
30. When substrate 10a was treated with base in boiling MeOH, the oxazolone ring opened up to give 10c. {A figure is presented}
31. Amide linkage of 11a was cleaved to give 11c. {A figure is presented}