4686-99-1Relevant articles and documents
Role of polar solvents for the synthesis of pillar[6]arenes
Santra,Kovalev,Kopchuk,Zyryanov,Majee,Charushin,Chupakhin
, p. 104284 - 104288 (2015/12/30)
An efficient procedure for the synthesis of pillar[6]arenes has been developed. The procedure involves the condensation of 1,4-dialkoxybenzenes and paraformaldehyde in the presence of a catalytic amount of H2SO4 or BF3·OEt2 in polar solvent media (acetonitrile, ethyl alcohol, acetone etc.). In all cases the interaction afforded pillar[6]arenes in high yields.
Monodisperse dialkoxy-substituted oligo(phenyleneethenylene)s
Stalmach, Ulf,Kolshorn, Heinz,Brehm, Isabella,Meier, Herbert
, p. 1449 - 1456 (2007/10/03)
Individual but connected synthetic routes for the preparation of the all-E-configured 2,5-dipropoxy-substituted oligo(1,4-phenyleneethenylene)s 1a-g were developed. An increasing number of conjugated stilbene units from n = 1 to n = 11 led to a convergent bathochromic shift (Δλ = λz - λ1 = 127 nm) in the UV/Vis absorption. An exponential function for the convergence of the absorption energies (wavelengths) in conjugated systems is proposed. By a simple extrapolation of this function the effective chain length may be determined. VCH Verlagsgesellschaft mbH, 1996.