One-Pot Synthesis of Symmetric Octithiophenes from Asymmetric β-Alkylsulfanyl Bithiophenes
摘要:
Starting from 4-(octylsulfanyl)-2,2'-bithiophene, 4-bromo-4'-(octylsulfanyl)-2,2'-bithiophene, 4-iodo-4'-(octylsulfanyl)-2,2'-bithiophene, 4-bromo-4'-[(S)-2-methylbutylsulfanyl]-2,2'-bithiophene, and 4-iodo-4'-[(S)-2-methylbutylsulfanyl]-2,2'-bithiophene, a new series of symmetrically beta-substituted octithiophenes were synthesized by one-pot oxidative coupling with FeCl3. The octithiophenes obtained are soluble in common organic solvents and show different solvatochromic properties depending on the substitution type. In particular, the bromine atom exerts a positive influence on the supramolecular organization: the brominated octithiophenes display high filmability, solvatochromism, and CD induced by aggregation (when the chiral 2-methylbutylsulfanyl group is present), properties usually observed for polythiophenes. Density functional theory (DFT) calculations were carried out an a model bithiophene (4-substituted with a methylsulfanyl group) in order to understand the possible mechanism of the growth, the regiochemistry, and the reason for the polymerization leads to an octithiophene.
One-Pot Synthesis of Symmetric Octithiophenes from Asymmetric β-Alkylsulfanyl Bithiophenes
摘要:
Starting from 4-(octylsulfanyl)-2,2'-bithiophene, 4-bromo-4'-(octylsulfanyl)-2,2'-bithiophene, 4-iodo-4'-(octylsulfanyl)-2,2'-bithiophene, 4-bromo-4'-[(S)-2-methylbutylsulfanyl]-2,2'-bithiophene, and 4-iodo-4'-[(S)-2-methylbutylsulfanyl]-2,2'-bithiophene, a new series of symmetrically beta-substituted octithiophenes were synthesized by one-pot oxidative coupling with FeCl3. The octithiophenes obtained are soluble in common organic solvents and show different solvatochromic properties depending on the substitution type. In particular, the bromine atom exerts a positive influence on the supramolecular organization: the brominated octithiophenes display high filmability, solvatochromism, and CD induced by aggregation (when the chiral 2-methylbutylsulfanyl group is present), properties usually observed for polythiophenes. Density functional theory (DFT) calculations were carried out an a model bithiophene (4-substituted with a methylsulfanyl group) in order to understand the possible mechanism of the growth, the regiochemistry, and the reason for the polymerization leads to an octithiophene.
Facile Preparation of Aryl Sulfides Using Palladium Catalysis under Mild Conditions
作者:Tatsuo Okauchi、Kouji Kuramoto、Mitsuru Kitamura
DOI:10.1055/s-0030-1259012
日期:2010.12
A convenient method for C-S cross-coupling of aryl bromides with various thiols has been developed that involves the use of a 1,1'-bis(diphenylphosphino)ferrocene (DPPF)-ligated palladium complex with N,N-diisopropylethylamine (DIPEA) as the base. This coupling is tolerant of a wide range of functional groups, including hydroxy, amino, cyano, nitro, formyl, and carboxyl groups.