Heterocycles 

About: Heterocycles is an academic journal published by Elsevier BV. The journal publishes majorly in the area(s): Bicyclic molecule & Catalysis. It has an ISSN identifier of 0385-5414. Over the lifetime, 13333 publications have been published receiving 140415 citations. The journal is also known as: international journal for reviews and communications in heterocyclic chemistry & International journal for reviews and communications in heterocyclic chemistry.

Cyclic Carboxylic Imide Structures as Structure Elements of High Stability. Novel Developments in Perylene Dye Chemistry

Abstract: Cyclic carboxylic imides are structure elements in aromatic heterocycles with high persistency. Their attachment to perylene leads to the perylene dyes; the synthesis and unique properties of the dyes are reported and discussed. An extension of the principle to other aromatics is made.

Recent developments of free-radical substitutions of heteroaromatic bases

Abstract: k R I + A r . * R. + A r I . k>109 M-~s ' (18) A l t h o x h ba th r e a c t i o n s gave good r e s u l t s i n many cases (Table 8), some l i m i t a t i o n s a re encountered wi th both r a d i c a l sources . Aroyl peroxides do r e a c t wi th t a l k p l iod ides , hu t do not produce t a l k y l rad i c a l s due t o i n compet i t ive i o n i c r e a c t i o n s . Moreover t h e thermal o r induced decomposition of a r o y l peroxides a t f i r s t produce aroyloxy r a d i c a l s , A r C O O , which r e a c t wi th s e v e r a l s u b s t r a t e s ( a c t i v a t e d aromatics, o l e f i n s , a lcohols , e t h e r s , amines) i n s t e a d o f gene ra t ing a r y l r a d i c a l s by decarboxyla t ion. HETEROCYCLES, Vol 28, No 1, 1989 The main limitation encountered with diazonium salts is due to the high addition rates of the nucleophilic radicals to the diazonium group, leading to the "free-radical diazo-coupling reaction" 27 (eq. 19). This competition can be in part restricted by keeping low the stationary concentration of the diazonium salt during the reaction. TABLE 8 Alkylation of heteroaromatic bases by diazonium salt, benzoyl peroxide and alkyl iodides 11 Heteroaromatic base Radical source Alkyl iodide Orientation Yield % a )

Nitriles in heterocyclic synthesis: novel synsthesis of benzo[c]-coumarin and of benzo[c]pyrano[3,2-c]quinoline derivatives

Abstract: Syntheses a partir de methyl-4 oxo-2 chromenecarbonitrile-3 ou de dihydro-5,6 dimethyl-4,6 dioxo-2,5 pyranno [3,2-c] quinoleinecarbonitrile-3, et d'α-cyano ou α-ethoxycarbonyl cinnamonitriles

Palladium-catalyzed arylation of furan, thiophene, benzo[b]furan and benzo[b]thiophene

Abstract: Treatment of π-electron sufficient aromatic heterocycles such as title compounds with aryl bromides in the presence of tetrakis(triphenylphosphine)palladium gave the corresponding 2-aryl aromatic heterocycles.