19190-91-1Relevant articles and documents
Synthesis of Blue-Luminescent Seven-Membered Phosphorus Heterocycles
Regulska, Elzbieta,Ruppert, Heiko,Rominger, Frank,Romero-Nieto, Carlos
, p. 1247 - 1252 (2020)
A facile synthetic procedure to prepare π-extended seven-membered phosphorus heterocycles, both symmetric and asymmetric, is reported. The prepared molecules present a persistent nonplanar framework and are soluble in a wide variety of solvents. The seven
PERI-BRIDGED NAPHTHALENES. 4. CHALCOGEN-BRIDGED ACENAPHTHYLENES
Chiang, Long-Yong,Meinwald, Jerrold
, p. 4565 - 4568 (1980)
Three new electron donors, acenaphtho-1,2-dithiole (1), acenaphtho-1,2-diselenole (2), and acenaphtho-1,2-ditellurole (3), can be prepared in 28percent, 22percent, and 14percent yields respectively by reaction of the elemental chalcogens (S, Se, Te) with 5,6-dilithioacenaphthylene (4).Compound 4 is generated by treatment of 5,6-dibromoacenaphthylene (5), for which a convenient preparation is described, with n-butyllithium(2 equiv.) in THF at -78 deg C.
Enhancement of Negative Photochromic Properties of Naphthalene-Bridged Phenoxyl-Imidazolyl Radical Complex
Abe, Jiro,Ito, Hiroki,Mutoh, Katsuya
, (2020)
Negative photochromism has increased attention as a light-switch for functional materials. A development of fast photochromic molecules has been also expected because a rapid thermal back reaction within a millisecond time scale is useful for real-time switching. Herein, we synthesized the derivatives of the naphthalene-bridged phenoxyl-imidazolyl radical complex (Np?PIC) showing the negative photochromism to demonstrate the efficient strategy to increase the visible light sensitivity and to control the thermal back reaction rates. The distances of the C?C bond of the transient 2,4’-isomer shows good agreement with the thermodynamic stability, leading to the control of the thermal back reaction rate. We revealed the cyclic voltammetry and the DFT calculations are efficient to predict the characters of the HOMO and LUMO. The introduction of the electron-withdrawing dicyanoquinodimethane group is efficient to induce the photochromic reaction with increased visible-light sensitivity by the expansion of the π-conjugation. The results will give an important insight for the future development of fast-responsive negative photochromic molecules.
Anomalous Halogen-Halogen Interaction Assists Radial Chromophoric Assembly
Niyas,Ramakrishnan, Remya,Vijay, Vishnu,Sebastian, Ebin,Hariharan, Mahesh
supporting information, p. 4536 - 4540 (2019/02/26)
The design of highly efficient supramolecular architectures that mimic competent natural systems requires a comprehensive knowledge of noncovalent interactions. Halogen bonding is an excellent noncovalent interaction that forms halogen-halogen (X2) as well as trihalogen interacting synthons. Herein, we report the first observation of a symmetric radial assembly of chromophores (R3c space group) composed of a stable hexabromine interacting synthon (Br6) that further push the limits of our understanding on the nature, role, and potential of noncovalent halogen bonding. Contrary to the destabilization proposed for Type-I X2 interactions, Br6-synthon-possessing Type-I X2 interactions exhibit a stabilizing nature owing to the exchange-correlation component. The radial assembly of chromophores is further strengthened by intermolecular through-space charge transfer interaction. Br6-synthon-driven 3-fold symmetric radial assembly render a lattice structure that reminisces the chromophoric arrangement in the light harvesting system 2 of purple bacteria.
