New and convenient synthesis of pyrrolo[1,2-a]benzimidazoles and indolizinones based on regioselective cyclization reactions of heterocyclic dianions

Synlett

Volumn , Issue 4, 1998, Pages 399-401

  Langer, Peter ^a   Döring, Manfred ^b  

^a UNIVERSITY OF GÖTTINGEN   (Germany)

^b FRIEDRICH SCHILLER UNIVERSITY JENA   (Germany)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001250164     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-1998-1673     Document Type: Article

References (37)

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22. 5: C. 79.64; H, 5.39; N, 14.97. Found: C, 79.84; H, 5.95; N, 15.50. For all dianion cyclizations reported herein, virtually no heterocyclic side products were formed. Some ether insoluble polymeric material was formed from which the product was separated by flash-chromatography. In some cases small amounts of ArNC (< 10 % yield) were isolated, which derive from reductive cleavage of the carbon-carbon bond of 2a,b.
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