Facile preparation of unsymmetric carbodiimides via in situ tin(II)-mediated heterocumulene metathesis

Journal of the American Chemical Society

Volumn 120, Issue 22, 1998, Pages 5585-5586

  Babcock, Jason R ^a   Sita, Lawrence R ^a  

^a UNIVERSITY OF CHICAGO   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CYANAMIDE;

CHEMICAL STRUCTURE; LETTER; PROTON NUCLEAR MAGNETIC RESONANCE; SYNTHESIS; UNITED STATES;

EID: 0032503566     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja980173c     Document Type: Article

References (37)

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28. 2 works equally well in this reaction.
29. 3.
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31. 2O, tetrahydrofuran, dichloromethane); however, pentane is preferred for volatile carbodiimide products.
32. The preparation and crystal structure of this compound will be reported elsewhere.
33. 3), has been used to conduct a Hammett study which revealed that the rate of heterocumulene metathesis is enhanced by electron-donating groups, and thus, these rates also parallel the nucleophilicities of these isocyanates.
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36. 2O and filtered through a 1 × 5 cm pad of silica gel on a glass frit. Removal of the volatiles provided the final crude product which was bulb-to-bulb distilled at 75 °C/35 mmHg to provide 0.918 g (5.92 mmol, 84%) of pure 1,3-bis(tert-butyl)carbodiimide as a colorless oil.
37. Divalent tin(II) compounds have been observed in the solid state as LiCl complexes, see: Arif, A. M.; Cowley, A. H.; Elkins, T. M. J. Organomet. Chem. 1987, 325, C11-C13.