ISSN:
0009-2940
Keywords:
Azirines
;
Oxazoles
;
Pyrrolines
;
Vinyl azides
;
Tetrazoles
;
Pyridines, tetrahydro-
;
Cyanoacrylates
;
Calculations, AM1
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Geminal Vinyl Diazides, X. - Methyl 3,3-Diazido-2-cyanoacrylate: Synthesis of Vinyl Azides, 4,5-Dihydro-1H-tetrazol-5-ylidenes, Oxazoles, and N-CyaniminesReaction of methyl 3,3-diazido-2-cyanoacrylate (1) with amines 2 at -30°C yields aminovinyl azides 4. In the presence of equivalent amounts of triethylamine the vinyl azides 4 undergo 1,5′-ring closure to afford the triethylammonium salts 5. Treatment of 5 with hydrochloric acid gives the corresponding 4,5-dihydro-1H-tetrazol-5-ylidene derivatives 6. In contrast thermolysis of 4 leads via azirines 7 to oxazoles 8. Reaction of vinyl diazide 1 with lysine and cystine, respectively, yields bis(vinyl azides) 9. Triethylamine-induced 1,5′-ring closure of 9 produces the bis(triethylammonium) salts 10, which can be transformed under acidic conditions into the corresponding bis(4,5-dihydro-1H-tetrazol-5-ylidene) derivatives 11. With methyl acrylate (17) oxazole 15 reacts via carbonyl ylide 16 in a 1,3-dipolar cycloaddition to give pyrroline 18 (X-ray structure analysis). Thermolysis of the geminal vinyl diazide 1 in the presence of alcohols 19 or primary amines 21 forms the cyanimines 20 and 22, respectively, via methyl 3-aza-2,3-dicyanoacrylate 25. 25 exists as syn/anti isomers which fully agrees with AM1 calculations carried out on cyanimine model systems.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19911240328
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