ChemInform Abstract: Some Reactions with vω‐Bromoacetophenone: Novel Synthesis of Polysubstituted Pyrrole, Furan, Pyridine, and Pyridazine Derivatives.

Abstract

ChemInform Abstract Coupling of vω-bromoacetophenone (I) with malononitrile (II) gives the phenacylmalononitrile (III) which is cyclized with trichloroacetonitrile (IV), forming the pyrrole (V). Treatment of (III) with AcOH/H2SO4 affords the furan (VI). Starting with the ketone (I), the Knoevenagel product (VII) is prepared, yielding the pyridine (X) via the derivative (IX). This produces also the furan (XI). (No yields given).

The Chemistry of α-Haloketones and Their Utility in Heterocyclic Synthesis

“…The reaction of α-bromoacetophenones with malononitrile ( 250 ) affords 2-amino-3-cyanofuran derivatives 251 . This reaction, aimed at heterocyclic synthesis of furans and their fused systems, was first reported by Gewald and subsequently explored by other groups ( Scheme 74 ) [ 490 , 491 , 492 , 493 , 494 , 495 , 496 , 497 , 498 , 499 , 500 , 501 ].…”

Phenacyl Bromides Revisited: Facile Synthesis of Some New Pyrazoles, Pyridazines, and Their Fused Derivatives

“…In the context of this program, we have previously reported several syntheses starting from 2‐bromo‐1‐phenylethanone (ω‐bromoacetophenone) 2a (obtained from acetophenone 1 by bromination; Fig. ) . Some new pyrrole, pyrazole, and pyridazine derivatives were required for such biological studies.…”

Heterosynthesis Using Nitriles: Novel Pyrrolo[2,3-<i>b</i>]pyridines

“…We have reported the synthesis of a variety of pyrrole, N-substituted pyrrole and fused-pyrrole derivatives of biological interest [9][10][11][12][13][14][15][16]. Recently some pyrrolo [2,3-b] pyridine derivatives were shown to be effective as inhibitors of tumor necrosis factor alpha [17].…”