331720-33-3Relevant academic research and scientific papers
Single-crystal-to-single-crystal topochemical polymerizations of a terminal diacetylene: Two remarkable transformations give the same conjugated polymer
Ouyang, Xi,Fowler, Frank W.,Lauher, Joseph W.
, p. 12400 - 12401 (2003)
Host-guest chemistry was used to prepare a cocrystal of a dipyridyl substituted oxalamide host and a resorcinol derivative of a terminal diacetylene. X-ray crystallography revealed that the molecules assemble into a triple-helix with the diacetylene functionalities aligned in the center of the helix. Upon heating, the diacetylenes polymerize to give the corresponding polymer. In a second experiment, the X-ray structure of the crystalline hydrate of the same diacetylene also showed a suitable alignment of the diacetylene functionalities. These crystals polymerize at only 50 °C with the C1 carbon end of the diacetylene undergoing an unprecedented 2.4 A inward swinging movement. This results in a remarkable 9% increase in crystal density. These are the first structurally characterized polymerizations of any terminal diacetylene. A detailed comparison of the two sets of structural changes offers an interesting insight into the precise trajectories of polymerization reactions. Copyright
Linear-dendritic poly(ester)-block-poly(ether)-block-poly(ester) ABA copolymers constructed by a divergent growth method
Lambrych, Kevin R.,Gitsov, Ivan
, p. 1068 - 1074 (2003)
The divergent synthesis of amphiphilic linear-dendritic block copolymers, LDBCs, that contain linear poly(ethylene glycol), PEG, and dendritic poly(benzyl ester)s is explored in this report. First [G1]- and second [G2]-generation LDBCs are constructed fro
Directing the crystallization of dehydro[24]annulenes into supramolecular nanotubular scaffolds
Suzuki, Mitsuharu,Kotyk, Juliet F. Khosrowabadi,Khan, Saeed I.,Rubin, Yves
supporting information, p. 5939 - 5956 (2016/06/09)
The self-assembly of a series of dehydro[24]annulene derivatives into columnar stacks has been examined for its latent ability to form -conjugated carbon-rich nanotubular structures through topochemical polymerizations. We have studied the parameters affe
SuFEx-based synthesis of polysulfates
Dong, Jiajia,Sharpless, K. Barry,Kwisnek, Luke,Oakdale, James S.,Fokin, Valery V.
supporting information, p. 9466 - 9470 (2014/11/07)
High-molecular-weight polysulfates are readily formed from aromatic bis(silyl ethers) and bis(fluorosulfates) in the presence of a base catalyst. The reaction is fast and proceeds well under neat conditions or in solvents, such as dimethyl formamide or N-methylpyrrolidone, to provide the desired polymers in nearly quantitative yield. These polymers are more resistant to chemical degradation than their polycarbonate analogues and exhibit excellent mechanical, optical, and oxygen-barrier properties. High-molecular-weight polysulfates are readily formed from aromatic bis(silyl ethers) and bis(fluorosulfates) in the presence of a base catalyst. The polymers were obtained in nearly quantitative yield under neat conditions, they are more resistant to chemical degradation than their polycarbonate analogues and exhibit excellent mechanical, optical, and oxygen-barrier properties. BPA=bisphenol A.
Construction of segregated arrays of multiple donor and acceptor units using a dendritic scaffold: Remarkable dendrimer effects on photoinduced charge separation
Li, Wei-Shi,Kim, Kil Suk,Jiang, Dong-Lin,Tanaka, Hiroyuki,Kawai, Tomoji,Kwon, Jung Ho,Kim, Dongho,Aida, Takuzo
, p. 10527 - 10532 (2007/10/03)
Dendritic molecules appended with multiple zinc porphyrin units (DP m, m [number of zinc porphyrin units] = 6, 12, and 24) trap bipyridine compounds carrying multiple fullerene units (Py2P n, n [number of C60 units] = 1-3), affording coordination complexes DPm?Py2Fn having a photoactive layer consisting of spatially segregated donor and acceptor arrays on their surface. Complexes DPm?Py2Fn are stable enough (K [average binding affinity] = 1.1 × 106-4.4 × 106 M-1 in CHCl3 at 25 °C) to be isolated by gel permeation chromatography. UHV-STM microscopy enables clear visualization of a petal-like structure of DP12?Py2F3. Photoexcitation of the zinc porphyrin units in DPm?Py 2Fn results in a zinc porphyrin-to-fullerene electron transfer to generate a charge separation. The charge-separation rate constant (kCS) in CH2Cl2 at 20 °C increases from 0.26 × 1010 to 2.3 × 1010 s-1 upon increment of m and n, whereas the charge-recombination rate constant (k CR) remains almost unchanged at 4.5 × 106-6.7 × 106 s-1. Consequently, DP24?Py 2F3 furnishes the largest ratio of kCS/k CR (3400) among the family.
Dendron rodcoils: Synthesis of novel organic hybrid structures
Zubarev, Eugene R.,Stupp, Samuel I.
, p. 5762 - 5773 (2007/10/03)
Convergent and divergent syntheses of novel organic hybrid structures termed dendron rodcoils (DRC) containing dendritic, rodlike, and coillike segments are described. The aryl ester dendron masked with 32 trifluoromethyl groups is prepared via a converge
Toward globular macromolecules with functionalized interiors: Design and synthesis of dendrons with an interesting twist
Bharathi, Pandi,Zhao, Hongda,Thayumanavan
, p. 1961 - 1964 (2007/10/03)
(formula presented) Design and synthesis of a novel class of monodendrons, in which the functional units can potentially be directed toward the concave interiors of dendrimers, are described. The key feature of the design is the placement of the amphiphil
Synthesis of (R)- and (S)-4'-acetoxyolivetol [(R)- and (S)-5-(4'-acetoxypentyl)-1,3-benzenediol]: Key intermediates in the synthesis of tetrahydrocannabinol derivatives
Singer,Siegel,Gordon,Dutta,Razdan
, p. 486 - 488 (2007/10/02)
The synthesis of (R)- and (S)-4'-acetoxyolivetols, key intermediates in the synthesis of tetrahydrocannabinol derivatives from 3,5-dihydroxybenzoic acid (4) is described. The 3,5-dihydroxy groups were protected as their tert-butyldimethylsilyl derivatives
