89004-92-2

Upstream product

• 89004-89-7 1,7-bis(o-ethynylphenyl)-3-(diphenylmethylene)-1,4,6-heptatriene 
• 117-34-0 2,2-diphenylacetic acid 
• 78072-27-2 1,7-bis-(o-ethynylphenyl)-1,4,6-heptatrien-3-one 
• 1871-76-7 diphenylacetic acid chloride 

Relevant academic research and scientific papers

Syntheses and Properties of Dimethyldiphenyltetradehydro-trideca-, -pentadeca-, -heptadeca-, -nonadeca-fulvene, and Benzannelated Pentadecafulvene Derivatives

Syntheses of 4,9-dimethyl-13-diphenylmethylene-5,6,7,8-tetradehydrocyclotridecene (7), 4,9-dimethyl-15-diphenylmethylene-5,6,7,8-tetradehydrocyclopentadecene (8), 6,11-dimethyl-17-diphenylmethylene-7,8,9,10-tetradehydrocyclopentadecene (9), and 6,11-dimethyl-19-diphenylmethylene-7,8,9,10-tetradehydrocyclononadecene (10) are described.Although examination of the 1H n.m.r. spectra suggested that all of the fulvenes (7)-(10) are atropic, the benzannelated derivatives of pentadecafulvene (8), i.e. 13-methyl-7-diphenylmethylene-14,15,16,17-tetradehydrobenzocyclopentadecene (25), 13-methyl-9-diphenylmethylene-14,15,16,17-tetradehydrobenzocyclopentadecene (26) and 7-diphenylmethylene-16,17,18,19-tetradehydrodibenzocyclopentadecene (27) were prepared in order to examine the tropicity of (8) more closely.Comparison of the 1H n.m.r. spectra of these benzannelated fulvenes (25)-(27) with that of 88) reveals that the nonbenzannelated fulvene 88) is atropic.The influence of benzannelation upon the structure of the molecular skeleton of the tetradehydropentadecafulvene system is also discussed.

SYNTHESES AND PROPERTIES OF BENZANNELATED DIPHENYLPENTADECAFULVENE DERIVATIVES

Synthesis of 10-methyl-16,16-diphenyl-4,5-benzo-6,8-bisdehydro- 4, 12-methyl-16,16-diphenyl-6,7-benzo-8,10-bisdehydro- 5, and 16,16-diphenyl-4,5:10,11-dibenzo-6,8-bisdehydropentadecafulvene 6, has been described.Comparison of 1H-NMR spectra of these benzannelated fulvenes 4-6 with that of nonbenzannelated fulvene 3 reveals that 5,10-dimethyl-16,16-diphenyl-6,8-bisdehydropentadecafulvene 3 is atropic.