65018-53-3Relevant academic research and scientific papers
A chiral probe for the asynchronous transition state of Diels-Alder reactions with acetylenedicarboxylate
Buckle, Ronald N.,Burnell, D. Jean
, p. 14829 - 14838 (1999)
Diels-Alder reactions took place with modest diastereoselectivity between dimethylcyclohexadiene derivative 3a and di-(-)-menthyl acetylenedicarboxylate, whereas the dimethylcyclohexadiene 2 showed no selectivity whatsoever. These results can be rationalized in terms of a complete lack of any endo-exo preference for the carboxylate groups and a more synchronous addition with 3a than with 2.
Highly Tactic Cyclic Polynorbornene: Stereoselective Ring Expansion Metathesis Polymerization of Norbornene Catalyzed by a New Tethered Tungsten-Alkylidene Catalyst
Gonsales, Stella A.,Kubo, Tomohiro,Flint, Madison K.,Abboud, Khalil A.,Sumerlin, Brent S.,Veige, Adam S.
, p. 4996 - 4999 (2016)
The tungsten alkylidyne [tBuOCO]W≡C(tBu) (THF)2 (1) reacts with CO2, leading to complete cleavage of one C=O bond, followed by migratory insertion to generate the tungsten-oxo alkylidene 2. Complex 2 is the first catalyst to polymerize norbornene via ring expansion metathesis polymerization to yield highly cis-syndiotactic cyclic polynorbornene.
CATALYST FOR RING EXPANSION METATHESIS POLYMERIZATION OF CYCLIC MONOMERS
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Page/Page column 4; 13; 14, (2017/04/11)
A tetraanionic OCO pincer ligand metal-oxo-alkylidene complex is prepared from a trianionic pincer ligand supported metal-alkylidyne. The metal can be tungsten or other group 5-7 transition metal. The tetraanionic pincer ligand metal-oxo-alkylidene comple
Stereospecific ring-opening metathesis polymerization of norbornadienes employing tungsten oxo alkylidene initiators
Forrest, William P.,Weis, Jonathan G.,John, Jeremy M.,Axtell, Jonathan C.,Simpson, Jeffrey H.,Swager, Timothy M.,Schrock, Richard R.
supporting information, p. 10910 - 10913 (2014/08/18)
We report here the polymerization of several 7-isopropylidene-2,3- disubstituted norbornadienes, 7-oxa-2,3-dicarboalkoxynorbornadienes, and 11-oxa-benzonorbornadienes with a single tungsten oxo alkylidene catalyst, W(O)(CH-t-Bu)(OHMT)(Me2Pyr) (
Synthesis of acetylenedicarboxylic acid esters and asymmetric Diels-Alder reactions of the bis(methyl (S)-lactyl) ester
Charlton, James L.,Chee, Gaiklean,McColeman, Heather
, p. 1454 - 1462 (2007/10/03)
A general method has been developed for the preparation of acetylenedicarboxylic acid esters and applied to the synthesis of both achiral and chiral esters.Diels-Alder reactions of one of the chiral esters, the bis(methyl (S)-lactyl) ester, with various types of dienes, such as phenylbutadiene, orthoquinodimethanes, and isobenzofuran, have been investigated.Moderate asymmetric induction was observed in reactions with dienes bearing an α-hydroxyl group.In one case, an unusual solvent-induced reversal of asymmetric induction was observed.Key words: acetylenedicarboxylic acid esters, phenylbutadiene, orthoquinodimethanes, isobenzofurans, Diels-Alder , asymmetric.
Synthesis of Chiral Esters of Acetylenedicarboxylic Acid
Charlton, James L.,Chee, Gaiklean
, p. 6243 - 6246 (2007/10/02)
A general method for the preparation of acetylenedicarboxylic acid esters has been investigated and several esters have been prepared in excellent yield.The bis-(methyl (S)-lactyl), bis-(methyl (R)-mandelyl), and bis-menthyl esters were prepared, as well as achiral diaryl and dialkyl esters.The esters were synthesized from the corresponding dibromofumarates by 2,3-dibromo elimination using zinc or zinc amalgam in THF at room temperature or at reflux.The dibromofumarates were prepared by the esterification of dibromofumaryl chloride with the corresponding alcohols.
