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Ethylene derivatives enamines

Curtius degradation 16, 560 enamines 16, 65 ethylene derivatives by reductoamination, ozonolytic 18, 530 ethyleneketones 18, 465 hydrazines s. N-Deamina-tion... [Pg.233]

Lithium tetrahydridoaluminate/aluminum chloride Ethylene derivatives from enamines... [Pg.327]

Via intermediates Synthesis of ethylene derivs. from enamines via thioenolethers a,y - thylene-y-lactone side-chain synthesis... [Pg.185]

Trimethylene dithiotosylate can react with activated methylene groups, enamines, or hydroxyethylene derivatives of carbonyl compounds to form dithiane derivatives. Ethylene dithiotosylate undergoes similar reactions to form dithiolanes.3 6... [Pg.89]

The procedure for the preparation of a dithiolane from a hydroxy-methylene derivative of a ketone and ethylene dithiotosylate (ethane-1,2-dithiol di-p-toluenesulfonate) can be varied to produce dithianes when the latter reagent is replaced by trimethylene dithiotosylate.8,4 The dithiotosylates also react with enamine derivatives to produce dithiaspiro compounds.4,5... [Pg.90]

The preparation of dithianes from enamines by reaction with trimethylene dithiotosylate (propane-1,3-dithiol di-p-toluenesulfonate) has been applied with enamines derived from oholostan 3 one, aceto-acetic ester, and phenylacetone.6 7 Reactions of trimethylene dithiotosylate with hydroxymethylene derivatives of ketones also give rise to dithianes thus the hydroxymethylene derivative of cholest-4-en-3-one can be converted to 2,2-(trimethylenedithio)cholest-4-en-3-one. 1,3-Dithiolanes are obtained in a similar manner by reaction of ethylene dithiotosylate1 with the appropriately activated substrate.5,7... [Pg.91]

In classical Hantzsch procedure, an enaminocarbonyl is formed in sim by condensation of ammonia source onto the 1,3-dicarbonyl substrate. But many groups have used a three-component modified-Hantzsch protocol in which the preformed enamine is introduced as a partner. Thus, utilization of cyclic or acyclic 1,3-dicarbonyl compounds, aldehydes, and acyclic or cyclic enamines has been reported, leading regioselectively to diversely substituted 1,4-DHP derivatives (Scheme 7). The sequence involving such starting materials was performed in numerous efficient systems, and more particularly in the following (1) microwave-assisted reaction in acetic acid [50], DMF [51], or an acetic acid/DMF system [52] (2) sonification in ethylene glycol [53] and (3) use of ionic liquids such as [bmim]BF4 [54]. [Pg.233]

The racemic polyzonimine (19) is prepared as shown in Scheme 33. The expoxide (314) is rearranged to the aldehyde (315) by refluxing with LiBr-HMPA in benzene. Morpholine enamine (316) derived from 315 is condensed with nitroethylene, generated in situ from 2-acetoxynitroethane, to afford the nitroaldehyde (317). Ethylene acetalization, reduction over Raney nickel, and subsequent deacetalization give ( )-polyzonimine (19) in 22% overall yield from the epoxide (314) 113). [Pg.259]

Octahydroazocine (1) behaves as a typical secondary amine and forms an azeotrope with water, b.p. 96 °C (52M386). It can be transformed into 1-nitroso and 1-amino derivatives in the usual way (74JMC948). The imine (1) can also be cyanoethylated, and adds ethylene oxide (59MI51900) to give the N- hydroxyethyl derivative. Attempts to convert (1) to an enamine by oxidation with silver acetate gave only a low yield of pyridine (52M386). [Pg.655]

Nucleophilic substitution and addition reactions of olefins are possible with Pd2 salts. A typical example is the formation of acetaldehyde by the reaction of ethylene with water (Wacker reaction). As nucleophiles, water, alcohols, phenols, carboxylic acids, amines, enamines, carbanions derived from active methylene compounds, and carbon monoxide react with olefins with stoichiometric consumption of Pd2 salts. [Pg.30]


See other pages where Ethylene derivatives enamines is mentioned: [Pg.228]    [Pg.244]    [Pg.220]    [Pg.298]    [Pg.350]    [Pg.296]    [Pg.319]    [Pg.419]    [Pg.257]    [Pg.261]    [Pg.206]    [Pg.282]    [Pg.287]    [Pg.247]    [Pg.260]    [Pg.288]    [Pg.240]    [Pg.240]    [Pg.240]    [Pg.303]    [Pg.81]    [Pg.365]    [Pg.133]    [Pg.240]    [Pg.415]   
See also in sourсe #XX -- [ Pg.18 , Pg.20 , Pg.67 , Pg.106 ]




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Ethylene derivatives enamines, synthesis

Ethylene derivs enamines, synthesis

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