A solid-phase synthesis of N,N′-disubstituted ureas and perhydroimidazo[1,5-a]pyrazines via the Curtius rearrangement

Organic Letters

Volumn 2, Issue 21, 2000, Pages 3309-3311

  Migawa, Michael T ^a   Swayze, Eric E ^a  

^a ISIS PHARMACEUTICALS   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0005676089     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol006383n     Document Type: Article

References (20)

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9. For references to this protecting group see: Greene T. W.; Wutz, P. G. M. Protective Groups in Organic Synthesis 3rd. Ed., John Wiley & Sons: New York, 1999; p 599.
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11. 1H NMR matched known values.
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14. Purchased from R. I. Chemicals, Orange, CA
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19. Reversing this sequence and installing the isocyanate first was unsuccessful, since cyclocleavage occurs during the Teoc deprotection.
20. 1H NMR analysis at 25 °C, 50 °C, and 95 °C indicated a mixture (∼1:1) of rotomers.