29536-30-9Relevant articles and documents
Making Waxy Salts in Water: Synthetic Control of Hydrophobicity for Anion-Induced and Aggregation-Enhanced Light Emission
Kim, Soohyung,Kim, Jongmin,Lee, Dongwhan
, p. 10858 - 10864 (2021)
We show that multipodal polycationic receptors function as anion-responsive light-emitters in water. Prevailing paradigms utilize rigid holes and cavities for ion recognition. We instead built open amphiphilic scaffolds that trigger polar-to-nonpolar environment transitions around cationic fluorophores upon anion complexation. This ion-pairing and aggregation event produces a dramatic enhancement in the emission intensity, as demonstrated by perchlorate as a non-spherical hydrophobic anion model. A synergetic interplay of C?H???anion hydrogen bonding and tight anion–π+ contacts underpins this supramolecular phenomenon. By changing the aliphatic chain length, we demonstrate that the response profile and threshold of this signaling event can be controlled at the molecular level. With appropriate molecular design, inherently weak, ill-defined, and non-directional van der Waals interaction enables selective, sensitive, and tunable recognition in water.
Regiospecific Synthesis of Aromatic Compounds via Organometallic Intermediates. 3. n-Alkyl-Substituted Benzene
Eapen, Kalathil C.,Dua, Sujan S.,Tamborski, Christ
, p. 478 - 482 (2007/10/02)
High molecular weight tri- and tetra-n-alkylbenzenes have been synthesized by the cross-coupling of the appropriate chlorinated benzenes with long-chain n-alkylmagnesium bromides using (1,2-bis(diphenylphosphino)ethane)nickel(II)chloride as catalyst.The reactions proceeded without any positional scrambling or alkyl group isomerization.A new method is described for the preferential substitution of one chlorine atom by an n-alkyl group in 1,3,5-trichlorobenzene.The reaction between an n-alkylmagnesium bromide and 1,3,5-trichlorobenzene catalyzed by Nickelacetylacetonate at low temperature and in tetrahydrofuran solvent favors monosubstitution.The cross-coupling reactions of these n-alkyldichlorobenzenes with other n-alkylmagnesium bromides, in the presence of NiCl2(dppe), proceeded at a much slower rate than those of 1,3,5-trichlorobenzene to yield the asymmetric 1,3,5-tri-n-alkylbenzenes.
