18076-62-5Relevant academic research and scientific papers
Azobenzene-tethered bis(trityl alcohol) as a photoswitchable cooperative acid catalyst for Morita-Baylis-Hillman reactions
Imahori, Tatsushi,Yamaguchi, Ryo,Kurihara, Seiji
supporting information; experimental part, p. 10802 - 10807 (2012/09/22)
Incorporation of an azobenzene core into tethered bis(trityl alcohol) allows the photoswitchable arrangement of the two trityl alcohol units through photoisomerization of azobenzene. The differently arranged trityl alcohol units change their cooperative function to reflect the positional relationships, and thus, the activity as a cooperative acid can be controlled by light stimuli (see figure). Copyright
2,2′-Dilithiobiphenyl by direct lithiation of biphenylene
Lillo, Victor J.,Gómez, Cecilia,Yus, Miguel
experimental part, p. 2266 - 2269 (2009/08/07)
The reaction of biphenylene (1) with an excess of lithium powder (1:14 molar ratio) and a catalytic amount of DTBB (10 mol %) in THF at room temperature leads to the formation of the dilithiated species I by reductive opening of the four-membered ring. Further reaction of this intermediate with different electrophiles [Electrophile = H2O, D2O, Me3SiCl, t-BuCHO, Et2CO, n-Pr2CO, (CH2)5CO, Ph2CO and adamantanone] at 0 °C yields the corresponding products 2, after hydrolysis with water. Cyclisation of some representative examples of compounds 2 with H3PO4 gives the corresponding dibenzoxepines 3.
Acid-catalyzed cyclization reactions of 2,2′ -bis(diarylhydroxymethyl)biphenyls to 5,5,7,7-tetraaryl-5,7-dihydrodibenzo[c,e]oxepins in the solid state
Hirano, Shinya,Toyota, Shinji,Toda, Fumio
, p. 749 - 756 (2007/10/03)
Heating of 2:1 inclusion crystals of 2,2′ -bis(hydroxydiphenylmethyl)biphenyl and formic acid in the solid state gave 5,5,7,7-tetraphenyl-5,7-dihydrodibenzo[c,e]oxepin in 89% yield. When mixtures of 2,2′-bis([bis(p-methoxyphenyl)hydroxymethyl]biphenyl and
Synthesis of highly hindered oxepins and an azepine from bis-trityl carbenium ions: Structural characterisation by NMR and X-ray crystallography
Carey, Kieran A.,Clegg, William,Elsegood, Mark R.J.,Golding, Bernard T.,Hill, M.N. Stuart,Maskill, Howard
, p. 2673 - 2679 (2007/10/03)
Reactions of the bis-carbenium ion 2,2′-bis[bis(p-methoxyphenyl)methyl]biphenyl ditetrafluoroborate with ammonia, n-propylamine and benzylamine have been studied with the aim of developing an acid-labile protecting group for primary amines that masks both
Complexation with Diol Host Compounds. Part 10. Synthesis and Solid State Inclusion Properties of Bis(diarylhydroxymethyl)-substituted Benzenes and Biphenyls; X-Ray Crystal Structures of Two Host Polymorphs and of a Non-functional Host Analogue
Weber, Edwin,Skobridis, Konstantinos,Wierig, Andreas,Nassimbeni, Luigi R.,Johnson, Louise
, p. 2123 - 2130 (2007/10/02)
A new family of host molecules where the molecular axis of usual 'wheel-and-axle' compounds is replaced by aromatic units is described.These diol hosts form crystalline inclusions with a variety of uncharged organic molecules mainly of a polar nature (53
REGIOSELECTIVE DIMETALLIERUNG VON AROMATEN. BEQUEMER ZUGANG ZU 2,2'-DISUBSTITUIERTEN BIPHENYLDERIVATEN
Neugebauer, Wolfgang,Kos, Alexander J.,Schleyer, Rague
, p. 107 - 118 (2007/10/02)
Lithiation of biphenyl with 2.4 mol of n-butyllithium in the presence of TMEDA led directly to the 2,2'-dilithio derivative (I) in modest, but preparatively useful yields.I, in turn, was converted to a variety of products.The activation of the 2'-position of 2-lithiobiphenyl was shown directly by a separate experiment.MNDO calculations indicate stabilization in I by double bridging and in 2-lithiobiphenyl by intramolecular ? interaction of Li with the o-phenyl group.Similar interactions in substitution transition states rationalize the specificity of the reactions observed.
