23746-57-8Relevant articles and documents
Organic zeolites from a diolefinic monomer
Guney-Altay, Ozge,Pestov, Dmitry,Tepper, Gary
, p. 13957 - 13962 (2007)
Submicrometer particles of diethyl p-phenylenediacrylate (EPA) with tunable molecular adsorption characteristics were produced by solid-state photopolymerization in the presence of template molecules. EPA monomer particles were produced by rapid expansion of supercritical solutions (RESS), and deposited directly onto surface acoustic wave (SAW) resonators. The EPA particles were photopolymerized directly on the SAW devices in the presence of molecular templates, and dynamic sorption isotherms of C1- through C9-alkanes were studied to characterize the particle-vapor interaction. The mass increase due to vapor uptake into the particulate coatings was measured by monitoring the SAW resonance frequency during vapor sorption. The vapor selectivity and molecular porosity of the particulate coatings were studied in situ on the piezoelectric substrate by measuring sorption isotherms. A gradual exclusion of smaller alkane molecules from the molecularly imprinted particulate coatings was observed with decreasing template molecule size. The observed selective and reversible adsorption of alkane analytes with different molecular sizes suggest that these imprinted polymers may be categorized as organic analogues of zeolites.
Piperidine-appended imidazolium ionic liquid as task-specific basic-IL for Suzuki and Heck reactions and for tandem Wittig-Suzuki, Wittig-Heck, Horner-Emmons-Suzuki, and Horner-Emmons-Heck protocols
Savanur, Hemantkumar M.,Kalkhambkar, Rajesh G.,Laali, Kenneth K.
, p. 150 - 161 (2017/06/30)
Facile, high yielding, one-pot methods for the synthesis of a library of diversely substituted bi-aryls, diarylethenes, and aryl-enoates, via Suzuki and Heck reactions, and by sequential Wittig-Suzuki, Wittig-Heck, Horner-Emmons-Suzuki, and Horner-Emmons-Heck reactions are reported. The reactions employ piperidine-appended imidazolium ionic liquid [PAIM][NTf2] as a task-specific basic-IL, butyl-methyl-imidazolium ionic liquid [BMIM][X] (X?=?PF6, BF4) as solvent, and catalytic amounts of Pd(OAc)2 with no other additives. Wittig and Horner-Emmons reactions are effected by reacting substituted benzaldehydes with 4-bromobenzyl-PPh3 (or bromomethyl-PPh3) phosphonium salts, or diethylphosphonate with bromobenzaldehydes respectively, to form the corresponding ethenes. Subsequent cross-coupling reactions are accomplished by addition of aryl-boronic acid or phenyl-ethenes along with Pd(OAc)2 to bring about the aforementioned hyphenated transformations. The feasibility to perform double-olefination via Wittig and Horner-Emmons reactions with dialdehydes to form highly conjugated bis-styryl and bis-enoate compounds is also shown. The [BMIM][X] solvent is recycled and reused.
Lewis Base Activation of Silyl Acetals: Iridium-Catalyzed Reductive Horner-Wadsworth-Emmons Olefination
Dakarapu, Udaya Sree,Bokka, Apparao,Asgari, Parham,Trog, Gabriela,Hua, Yuanda,Nguyen, Hiep H.,Rahman, Nawal,Jeon, Junha
supporting information, p. 5792 - 5795 (2015/12/11)
A Lewis base promoted deprotonative pronucleophile addition to silyl acetals has been developed and applied to the iridium-catalyzed reductive Horner-Wadsworth-Emmons (HWE) olefination of esters and the chemoselective reduction of the resulting enoates. Lewis base activation of silyl acetals generates putative pentacoordinate silicate acetals, which fragment into aldehydes, silanes, and alkoxides in situ. Subsequent deprotonative metalation of phosphonate esters followed by HWE with aldehydes furnishes enoates. This operationally convenient, mechanistically unique protocol converts the traditionally challenging aryl, alkenyl, and alkynyl esters to homologated enoates at room temperature within a single vessel.
