197958-38-6

Basic information

• Product Name: (E)-2-(2',4'-dimethylphenyl)pent-3-ene
• Synonyms: (E)-2-(2',4'-dimethylphenyl)pent-3-ene
• CAS NO: 197958-38-6
• Molecular Weight: 174.286
• Mol File: 197958-38-6.mol
• Article Data: 1

Chemical Properties

• CAS DataBase Reference: (E)-2-(2',4'-dimethylphenyl)pent-3-ene(CAS DataBase Reference)
• NIST Chemistry Reference: (E)-2-(2',4'-dimethylphenyl)pent-3-ene(197958-38-6)
• EPA Substance Registry System: (E)-2-(2',4'-dimethylphenyl)pent-3-ene(197958-38-6)

Safety Data

• Hazardous Substances Data: 197958-38-6(Hazardous Substances Data)

Upstream product

• 1458-99-7 4-chloropent-2-ene 
• 583-70-0 1-bromo-2,4-dimethylbenzene 
• 56535-63-8 (E)-4-bromopent-2-ene 
• 34589-46-3 (2,4-dimethylphenyl)magnesium bromide 

Relevant articles and documents

Conjugative interaction in styrenes

Conjugative interactions of the carbon-carbon double bond are fundamental in organic chemistry. In this work, equilibria are established among conjugated and unconjugated isomers of two β-substituted styrenes, 1-phenylbut-1-ene and 1-phenyl-3-methylbut-1-ene, and one α,β-disubstituted styrene, 2-phenyl-5-methylhex-2-ene, over a range of temperatures (the van't Hoff method) in hexamethylphosphoric triamide and potassium tert-butoxide. From the trans styrenes of the first two sets, an enthalpy of conjugative interaction of phenyl vis-a-vis alkyl (ΔΔH(ConjInter/Alk)) = -2.5 ± 0.2 kcal/mol [-5.1 kcal/mol defined as phenyl vis-a-vis hydrogen (ΔΔH(ConjInter/H))] is observed, while the cis styrenes reveal an attenuated ΔΔH(ConjInter/Alk) of -1.1 kcal/mol (ΔΔH(ConjInter/H)) = -2.7 kcal/ mol). The α-methyl group in the third set also leads to a reduced conjugative interaction. Entropy plays an important role in determining positions of equilibrium. Free energies of conjugation are reported for several sterically hindered o-methyl-substituted styrenes.