Ethylidene Oxide

Ethylidene Diethyl Ether. See Acetal A13-L Ethylidene Oxide. See Acetaldehyde A14-L Ethylidene-(2,4,6- trinitrophenyl hydrazine). 

In 1953 the Celanese Corporation of America introduced a route for the production of vinyl acetate from light petroleum gases. This involved the oxidation of butane which yields such products as acetic acid and acetone. Two derivatives of these products are acetic anhydride and acetaldehyde, which then react together to give ethylidene diacetate (Figure 14.2.)... 

However, the proposed in vivo transformation of anhydrovobasinediol to gelsemine might involve a series of more extensive alterations of the molecular skeleton which presumably would include (1) oxidation of the 2,7 double bond, (2) an acid-induced 2,7 shift, and (3) allylic rearrangement of the C-20 ethylidene side chain to a C-20 vinyl, so that a humantenine-type precursor... 

The photocyclization of enamides has been widely employed in the construction of heterocyclic systems the N-acryloyl-2-aminopyridines 37, for example, are converted on irradiation to the lactams 38.36 Numerous benzylisoquinoline alkaloids have been prepared using this approach, and in particular, the syntheses of benzo[c]phenanthridine alkaloids have been reviewed.37 Thus, irradiation of the [Z]-l-ethylidene-2-benzoyltetra-hydroisoquinoline 39 affords the corresponding 8-oxoberberine 4038 competing photoisomerization to the E-isomer is observed but cyclization occurs only via the Z-isomer. Examples of syntheses of Amaryllidaceae and indole alkaloids have also been reported. In this way, the precursor 41 of ( )-lycoran has been obtained by oxidative cyclization of the enamide 42.39... 

Figure 8.10 shows the application of SFG on adsorbed hydrocarbons [35], Ethylene was adsorbed on the (111) surface of platinum at 240 K, and subsequently heated to different temperatures. The spectra monitor the conversion of di-G bonded ethylene to ethylidyne (=C-CH3), via an intermediate characterized by a frequency of 2957 cm-1 attributed to the asymmetic C-H stretch of a CH3 group in the ethylidene (=CH-CH3) fragment. Somoijai and coworkers have demonstrated the usefulness of the SFG technique for in situ work with studies of ethylene hydrogenation and CO oxidation at atmospheric pressure [36]. 

The most interesting ethylene oxide derivative of the hexitols encountered hitherto is 1,2 5,6-dianhydro-D-mannitol. This was obtained in the form of its 3,4-isopropylidene (LXXXVIII) and 3,4-ethylidene (LXXXIX) derivatives.72 The isopropylidene compound was synthesized from l,6-dichloro-l,6-didesoxy-D-mannitol through its conversion first into l,6-dichloro-l,6-didesoxy-3,4-isopropylidene-D-mannitol. This,... 

D-Gulose (d-9) has also been prepared24 by the oxidation of 4,6-0-ethylidene-l,2-0-isopropylidene-a-D-galactopyranose (33), followed by reduction (resulting in overall inversion of the configuration of C-3) and hydrolysis. 

The simple cleavage of lactones 1 or 2 with alcohol and acid has not been reported. However, when 1 is treated with benzaldehyde diethyl acetal and hydrochloric acid, ethyl 3,5 4,6-di-0-benzylidene-L-gulonate (47) is formed in >90% yield.77,78 No other isomers were observed, and other acetals of benzaldehyde, as well as aliphatic aldehydes, afford similar products in good yield.77 D Addieco prepared36 similarly protected derivatives of L-gulonic acid by oxidation of l,3 2,4-di-0-ethylidene-D-glucitol (15), followed by esterification of the resulting acid with diazomethane. 

Steele, W.V., Chirico, R.D., Cowell, A.B., Knipmeyer, S.E., and Nguyen, A. Thermodynamic properties and ideal-gas enthalpies of formation for 2-aminoisobutyric acid (2-methylalanine), acetic acid, ( -5-ethylidene-2-norbornene, mesityl oxide (4-methyl-3-penten-2-one), 4-methylpent-l-ene, 2,2 -bis(phenylthio)propane, and glycidyl phenyl ether (1,2-epoxy-3-phenox3q>ropane), / Chem. Eng. Data, 42(6) 1053-1066, 1997. 

Dimerization of methyl crotonate has been carried out with alkaline earth metal oxides as basic catalysts 15). The reaction proceeds by Michael addition, which is initiated by abstraction of an allylic hydrogen of methyl crotonate by the basic site to form the allylic carbanion, which attacks a second methyl crotonate molecule at the jS-position to form a methyl diester of 3-methyl-2-vinylglutaric acid. The diester undergoes a double bond migration to form the final E- and Z- isomers of 3-ethylidene-3-methylglutaric acid dimethyl ester (MEG) (Scheme 22). 

Oxidation of trows-RuCl(C=CCH Ph2)(dppe)2 favors hydrogen atom transfer leading to frons-[RuCl(=C=CHCHPh2)(dppe)2] [217]. Chemical oxidation of Ru (C=CRc)(PPh3)2Cp (Rc = ruthenocenyl) gives the cydopentadienylidene-ethylidene... 

Das durch Pcriodat-Oxidation von 0-Acetoxy-N-(l-amino-ethyliden)-hydroxylaminen erhsilt-liche 1-Hydroximino-l-nitroso-ethan setzt sich mit Benzylhalogeniden zu 3-Aryl-5-methyl-l,2,4-oxadiazol-4-oxiden um56 ... 

In the 1940 s, in addition to these operations, two other processes became important. Acetic acid was made by reacting methanol with carbon monoxide, and acetic anhydride was being made by the ethylidene diacetate process, which in effect is the dehydration of acetic acid to the anhydride by the use of acetylene. Fermentation ethyl alcohol was converted to acetic acid via acetaldehyde as well as by the direct oxidation of ethyl alcohol. A new operation on the Gulf Coast was also based on acetaldehyde. However, the acetaldehyde is made by the direct oxidation of liquefied petroleum gas. A further process for the production of these materials, in which acetaldehyde is oxidized in one step to a mixture of anhydride and acid, was also begun. 

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