Ethers ethenyl

However, most asymmetric 1,3-dipolar cycloaddition reactions of nitrile oxides with alkenes are carried out without Lewis acids as catalysts using either chiral alkenes or chiral auxiliary compounds (with achiral alkenes). Diverse chiral alkenes are in use, such as camphor-derived chiral N-acryloylhydrazide (195), C2-symmetric l,3-diacryloyl-2,2-dimethyl-4,5-diphenylimidazolidine, chiral 3-acryloyl-2,2-dimethyl-4-phenyloxazolidine (196, 197), sugar-based ethenyl ethers (198), acrylic esters (199, 200), C-bonded vinyl-substituted sugar (201), chirally modified vinylboronic ester derived from D-( + )-mannitol (202), (l/ )-menthyl vinyl ether (203), chiral derivatives of vinylacetic acid (204), ( )-l-ethoxy-3-fluoroalkyl-3-hydroxy-4-(4-methylphenylsulfinyl)but-1 -enes (205), enantiopure Y-oxygenated-a,P-unsaturated phenyl sulfones (206), chiral (a-oxyallyl)silanes (207), and (S )-but-3-ene-1,2-diol derivatives (208). As a chiral auxiliary, diisopropyl (i ,i )-tartrate (209, 210) has been very popular. 

The methyl 2-(l//-pyrrol-2-yl)ethenyl ethers 1269, derived from enyne-imines and Fischer carbene complexes, were unstable with respect to air oxidation and were hydrolyzed to the corresponding ketones 1270 for characterization purposes (Equation 278) <20030L2043>. 

Nonenal E21d, 3348 (Allyl-ethenyl-ether + R3Al) 3350 ([3.3]-sigmatr. Rearrangem.)... 

Allyl-ethenyl-ether + R3AI) 2-Decenal XIII/2a, 321, 323, 372,... 

Allyl-ethenyl-ether 4- (H3C)3AI] Ethan 2-Cyclohexyl-l-ethoxy- E19a, 535 (En + Cyclohexan)... 

Significant progress has been made towards the understanding of proton delivery 152,165 Diastereomeric silyl ethenyl ethers 145 and 148 decompose on addition of TBAF and AcOH into the corresponding enols 146 and 149, which yield with AcOH two complementary bicyclic ketones (147 and 150, respectively), in different degrees of diastereomeric purity (equations 40 and 41). Two different proton transfer processes take place Bicyclic ketone 147 is formed by external delivery of a proton to 146 on its less hindered face (equation 40) the complementary ketone 150 is formed by protonation of 149 on its more hindered face (equation 41), invoking internal proton dehvery from the intermediate pyridinium acetate 151. For a more sterically demanding and weaker acid, such as phenol, the diastereoselectivity increased for 147 but reversed for 150. ... 

Whereas inter- and intramolecular Diels-Alder reactions normally require electron-deficient dienophiles, the 67r-electrocyclization proceeds with a large vaiiety of substituents on a hexatriene. In one such approach, the intramolecular Heck-type reaction of a 2-bromo-1 -en-(ft> — l)-yne 66 is used as a trigger to initiate an intermolecular Heck coupling with an alkene to form the conjugated 1,3,5-hexatriene 67 which eventually cyclizes in a 67T-electrocyclic process (Scheme 3-21) [173]. In many cases, aromatization of the cyclohexadiene 68 formed primarily occurs to yield carbo- and heterobicyclic compounds of type 70 [173a,b]. But with alkyl ethenyl ethers the cyclohexadienes 69 can be obtained in moderate yields [173b]. 

Other masked ethynyl groups including dihaloethenyls [54b],ethenyl ethers [58] and terminally substituted acetylenes [59] have also been applied in the pyrolytic preparation of PAHs, presumably also via carbene intermediates [60]. Furthermore, the combination of the different synthetic strategies is also possible, as demonstrated by the first successful synthesis of benzocorannulene (28, Scheme 10, [54 g]) and other PAHs. 

The interaction of an ethenyl ether and a trialkyl phosphite (trimethyl phosphite was actually used) under dry acid conditions (HCl gas in MeOH) leads to a phosphonic diester according to Scheme 2. Little dealkylation of the phosphite triester appears to occur, and the reaction appears therefore not to involve addition of dialkyl hydrogenphosphonate (the product of phosphite dealkylation), all the more so since triphenylphosphine also reacts under the same conditions to give related triphenylphosphonium salts. Ethenyl ethyl ether, 2,3-dihydrofuran and 2,3-dihydropyran were used as substratesThe ease of reaction under mild conditions, coupled with high yields, testifies to the importance of a cationic intermediate species. 

SYNONYMS vinyl 2-chloroethyl ether, (2-chloroethoxy) ethene, 2 -chloroethyl ethenyl ether, 2-ehloroethylvinylether, 2-chloroethylvinyl ether, 2-Vinyloxyethyl chloride... 

Chloroethylene polymer. See Polyvinyl chloride Chloroethylenevinyl acetate polymer. See Vinyl chloride/vinyl acetate copolymer 2 -Chloroethyl ethenyl ether. See 2-Chloroethyl vinyl ether... 

Synonyms 2-Chlorethyl vinyl ether (2-Chloroethoxy) ethene 2 -Chloroethyl ethenyl ether Ethene, 2-chloroethoxy- Ether, 2-chloroethyl vinyl... 

This reaction has been developed and uses a common iridium catalyst for the conversion [102], This process is also attractive as it could be used to generate ethenyl ethers This is a challenging reaction and has been accomplished through copper-catalyzed cross-coupling chemistry using a trivinylcyclotriboroxane as a vinylboronic acid equivalent [108]. It has also been achieved using iridium catalysis [102]... 

Athen, n. ethene (ethylene), -yl, n. ethenyl. Ather, m. ether (in older names frequently equivalent to ester). atberilhnlich, a. ether-Uke, ethereal. 

Bis(2-diisopropylaminoethyl) Disulfide Bis(2-diisopropylaminoethyl) Sulfide Bis(2-fluoroethyl) 2-Chloroethylamine Bis(2-fluoroethyl)methylamine Bis(2-hydroxyethyl) Sulfide Bis(2-hydroxyethyl) Thioether Bis(2-hydroxyethyl)amine Bis(2-hydroxyethyl)methylamine Bis(2-propenyl) Sulfide Bis(bromomethyl) Ether Bis(chloromethyl) Ether Bis(cyclohexyl)carbodiimide Bis(ethenyl)sulfone Bis(trichloromethyl) Carbonate Bis(/3-bromoethyl) Sulfide Bis(/3-chloroethyl)ethylamine Bis(/3-Chloroethyl)methylamine Bis(/3-chloroethylthio)ethane Bis(/3-mercaptoethyl) Sulfide... 

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