Ethylidene-acetone

The limitations of the reaction consist in the nonavailability of suitably substituted 2-buten-l-ones (78), in the moderate yields (usually up to 40%) and poor purity of the products, and in the fact that in most cases at least three substituents are required in positions 2, 4, and 6 of the resulting pyrylium salt for its isolation. Ethylidene-acetone (78, R = Me, R = H) and crotonaldehyde (78, R = H, R =Me) failed to yield pyrylium salts on acetylation with AcCl-I-AlClg however, acetylation with AC2O+HCIO4 of jS-hydroxyaldehyde... 

The present procedure for the preparation of acetone-anil is described by Reddelien. A reaction at lower temperature is reported by Craig, who also describes the alkaline decomposition of the anil to 2,4-dimethylquinoline and methane and gives a method of purification of the final product. Other methods for the preparation of 2,4-dimethylquinoline involve the Beyer synthesis from aniline hydrochloride and ethylidene acetone, a modification of this synthesis, or the Combes synthesis from acetyl-acetone and aniline. 

Ethylidene Acetone, Methylpropenyl Ketone or S-Pentene-ion CHg.CHiCH.-CO.CHg ... 

D.27) 3-Penten-2-one, ( )-, (E)-pent-3-en-2-one, methylpropenyl ketone, trans-2-penten-4-one, ethylidene acetone [3102-33-8] (Z)-13102-32-7] no stereochemistry [625-33-2] FEMA 3417... 

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.)... 

Dimethyl peroxide Diethyl peroxide Di-t-butyl-di-peroxyphthalate Difuroyl peroxide Dibenzoyl peroxide Dimeric ethylidene peroxide Dimeric acetone peroxide Dimeric cyclohexanone peroxide Diozonide of phorone Dimethyl ketone peroxide Ethyl hydroperoxide Ethylene ozonide Hydroxymethyl methyl peroxide Hydroxymethyl hydroperoxide... 

Another transformation observed with a naturally occurring bacteriochlorin is the tautomer-ization of the exocyclic C — C double bond in bacleriochlorophyll b (3) in acetone which gives 7,8-dehydrobacteriochlorophyll a (4), a chlorin-type product (configurations at C7 and of the 8-ethylidene group have not been established).112,12... 

Dimethyl peroxide Diethyl peroxide Di-t-butyl-di-peroxyphthalate Difuroyl peroxide Dibenzoyl peroxide Dimeric ethylidene peroxide Dimeric acetone peroxide Dimeric cyclohexanone peroxide Diozonide of phorone Dimethyl ketone peroxide Ethyl hydroperoxide Ethylene ozonide Hydroxymethyl methyl peroxide Hydroxymethyl hydroperoxide 1-Hydroxyethyl ethyl peroxide 1 -Hydroperoxy-1 -acetoxycyclodecan-6-one Isopropyl percarbonate Isopropyl hydroperoxide Methyl ethyl ketone peroxide Methyl hydroperoxide Methyl ethyl peroxide Monoperoxy succinic acid Nonanoyl peroxide (75% hydrocarbon solution) 1-Naphthoyl peroxide Oxalic acid ester of t-butyl hydroperoxide Ozonide of maleic anhydride Phenylhydrazone hydroperoxide Polymeric butadiene peroxide Polymeric isoprene peroxide Polymeric dimethylbutadiene peroxide Polymeric peroxides of methacrylic acid esters and styrene... 

Scheme 14.—Proposed Mechanism for Photochemical Reaction of Methyl 3,4-0 Ethylidene-/3-L-arabinopyranoside (35) with Excited Acetone.

The conversion of benzylidene and ethylidene derivatives into hydroxy benzoates and hydroxy acetates, respectively, following irradiation in acetone, and preferably in the presence of oxygen, was discussed by Binkley. Irradiation is carried out at a shorter wavelength (compared to 2-nitrobenzylidene derivatives) and the yields are significantly lower. 

The two possible homologues, with either one or two methyl groups on the methylene carbon of the methylenedioxy group of MDA, are also known. The ethylidene compound (the acetaldehyde addition to the catechol group) has been encoded as EDA, and the acetone (isopropylidine addition to the catechol group) is... 

Hydrochloric acid in boiling aqueous acetone accomplishes debenzyliden-ation,218-214 deacetonation,216 and simultaneous deacetonation and detritylation,206 216 all without desulfonylation. Hydrochloric acid in aqueous methanol causes (without desulfonylation) deacetonation,167 169 210 and, more rapidly, de-ethylidenation.167 Deacetonation, without desul-fonylation, has also been brought about with hydrochloric acid in aqueous dioxane194 or aqueous acetonitrile,217 and with 0.5 N aqueous hydrochloric act d.40 218 Aqueous hydrochloric acid (0.1 N) has also been used for de-ethylidenation.194... 

Treatment of the monoethylidene-D-mannitol with lead tetraacetate or periodate resulted in the consumption of two molecular equivalents of oxidant with the concomitant production of one mole of formaldehyde, one mole of formic acid and a monoethylidene-D-erythrose, the latter being identified by its conversion into the known crystalline D-erythrosazone.118 This evidence limited the choice of structure for the mannitol acetal to the 1,3- and 2,3-compound (4,6- and 4,5- are the respective identical structures). Two additional facts eliminated the latter alternative, first, the tetratosyl ester gave only one mole of sodium p-toluenesulfonate when heated with sodium iodide in acetone, and secondly, the same monoethylidene-D-mannitol was obtained from the above 1,3,4,6-diethylidene-D-mannitol by acidic hydrolysis.118 For these reasons Bourne, Bruce and Wiggins118 assigned to the mono-, di- and tri-ethylidene-D-mannitols, respectively, the 1,3-, 1,3 4,6- and 1,3 2,5 4,6- structures. 

Figure 3. ESR spectrum of the 2-ethylidene-l,3-dioxolan radical cation center indicated by a triangle. The radical cation has large CH3 splittings note, e.g., the well resolved second-order components. The size of the CH3 coupling, 2.511 mT, indicates that the unpaired spin resides mainly on the carbon atom next to the CH3 group. Experimental conditions photolytic flow system, aqueous solutions of pH 5 at 3°C containing 0.3 m acetone, 0.02 m K2S2O8, and 0.03 m 2-(l-bromoethyl)-1,3-dioxolan. From Ref. [79].

An important aspect in the development of this process is the understanding of by-product formation, as a means of implementing specific ways to minimize side reactions. The important by-products are ethylidene diacetate, acetone, carbon dioxide, methane, and heavy ends. 

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