Synthesis and X-ray structure of 1,4-bis[4-(N,N-dimethylamino)phenyl]buta-1,3-diyne: charge-transfer complex with acceptors

Abstract

4-(N,N-dimethylamino)phenylethyne has been satisfactorily prepared by the Wittig reaction between chloromethylene(tripheny1)phosphine ylide and 4-(N,N-dimethylamino)benzaldehyde, followed by hydrochloric acid elimination. 1,4-Bis [4-(N,N-dimethylamino)phenyl]-buta-l,3-diyne was obtained by oxidative dimerization in good yield. The dimer forms a 1 : 1 charge-transfer complex with TCNE, an X-ray structure analysis of which is reported.

Pre‐existing left pulmonary artery stenosis and other anomalies associated with device occlusion of patent ductus arteriosus

“…These results permit us to consider two important questions: (1) the sterical volume of the acetylene substituent shows some difficulties for the advancement of the cyclotrimerization but not for the polymerization reaction, and (2) the polymerization versus cyclotrimerization mechanism recently proposed by us is here reinforced 12…”

“…Arylacetylenes often yield cyclooligomers and polymers having low molecular masses with Ziegler–Natta catalysts. The polymer/cyclooligomer ratios are dependent on the catalyst, solvent, and monomer structure 12. Polyphenylacetylene shows interesting physical properties 1, 13–15.…”

The [2+2] Cycloaddition‐Retroelectrocyclization (CA‐RE) Click Reaction: Facile Access to Molecular and Polymeric Push‐Pull Chromophores

“…Thus,the transformation with p-methoxyphenyl-substituted alkyne 9 required heating to 110 8 8C, with the desired TCBD 12 obtained in 42 %y ield. [18] We corrected these wrong assignments by measuring the X-ray crystal structures of the donor-substituted, nonplanar TCBD products. In contrast, the reaction of p-N,N-dimethylanilino (DMA) substituted alkyne 11 proceeded rapidly at 20 8 8Ct op roduce the corresponding TCBD 14 in 100 % yield.…”

Polymerization of conjugated 5‐[(5‐ethynyl‐1‐naphthyl)ethynyl]‐N,N‐dimethylnaphthalen‐1‐amine with rhodium and palladium complexes

“…The results obtained in the polymerization of 3 with the palladium catalyst permitted the consideration of two important facts related to the naphthylacetylene coordination mechanism: (1) the volume of the naphthyl substituent in the acetylene showed an important hindering effect, preventing the advancement of the cyclotrimerization process but not the polymerization reaction, and (2) the mechanistic coincidence for the polymerization versus the 1,3,5‐cyclotrimerization recently proposed by us was here reinforced 23(a), 33…”