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Nencki reaction

The temperature must be carefully regulated, and in no case must it exceed 150°. In this preparation, as well as in the preparation of other ketones by the Nencki reaction, higher temperatures lead to the formation of a highly colored and resinous product which probably contains a little diketone. [Pg.41]

Nencki Reaction Acylation of polyphenolic compounds. Example ... [Pg.254]

NENCKI REACTION. The ring acylation of phenols with acids in the presence of zinc chloride, or the modification of the Friedel-Crafls alkylarioii-acylaliun procedure by substitution of ferric chloride for aluminum chloride. [Pg.1063]

Nencki reaction conditions, followed by partial methylation, phase-transfer catalyzed Baker-Venkataraman reaction with veratroyl chloride, and photocyclization. An outline of this method is depicted in Scheme 8. [Pg.48]

This reaction is related to the Friedel-Crafts Alkylation, Darzens Olefin Acylation, Fries Rearrangement, Haworth Phenanthrene Synthesis, and Nencki Reaction. [Pg.1128]

This reaction was first reported by Nencki et al. in 1881. It is the preparation of an acyl phenol derivative by zinc chloride-activated acylation between a phenol and an acyl chloride, anhydride, or even a carboxylic acid. Therefore, this reaction is generally known as the Nencki reaction. The Nencki reaction generally takes place with at least one equivalent of zinc chloride however, it does not involve the formation of a complex between zinc chloride and acyl chloride or anhydride in a manner similar to that of aluminum chloride. It has been found that the regioselectivity in preference of para-acylation decreases when the size of the acylating reagent increases." ... [Pg.2035]

A new mechanism is proposed here to illustrate the Nencki reaction from acyl anhydride, with the preference of para-acylation and the requirement of at least one equivalent of ZnCl2. [Pg.2035]

Other references related to the Nencki reaction are cited in the literature. ... [Pg.2037]

Nazarov Cyclization Reaction Neber Rearrangement Nef Reaction Nef Synthesis Negishi Cross Coupling Nencki Reaction... [Pg.11]

Synthetic applications D. Villemin, B. Labiad, Synth. Commun. 22, 3181 (1992) S. Nakanishi etal., ibid. 28,1967 (1998). Cf. Friedel-Crafts Reaction Nencki Reaction Nenitzescu Reductive Acylation. [Pg.211]

Preparation by condensation of salicylic acid with hydroquinone in the presence of zinc chloride for 45 min at 125-140° (Nencki reaction). - Refer to Chem. Abstr., 44, 1271f(1950)T... [Pg.26]

Preparation by reaction of benzoic acid with 2-propyl-resorcinol in the presence of zinc chloride at 150° for 2.5 h (62%) [1242] (Nencki reaction). [Pg.384]

Also obtained by reaction of acetic add on 2-bromo-resorcinol with zinc chloride (Nencki reaction) (26%) [1840]. [Pg.682]

Preparation by reaction of acetic acid on 4-chlororesorcinol with zinc chloride at 145° (Nencki reaction) (31%) [1988]. [Pg.690]

Preparation by reaction of acetic acid on phloroglucinol with zinc chloride (Nencki reaction), and then saponification of 5,7-dihydroxy-4-methylene-2-(2,4,6-trihydroxyphenyl)-4//-benzopyran first formed (76%) [2429],... [Pg.723]

See other pages where Nencki reaction is mentioned: [Pg.612]    [Pg.659]    [Pg.879]    [Pg.2035]    [Pg.2036]    [Pg.196]    [Pg.212]    [Pg.212]    [Pg.12]    [Pg.25]    [Pg.31]    [Pg.32]    [Pg.36]    [Pg.40]    [Pg.401]    [Pg.402]    [Pg.402]    [Pg.404]    [Pg.707]    [Pg.711]    [Pg.714]    [Pg.716]    [Pg.719]    [Pg.721]   
See also in sourсe #XX -- [ Pg.254 ]

See also in sourсe #XX -- [ Pg.1067 ]

See also in sourсe #XX -- [ Pg.321 ]

See also in sourсe #XX -- [ Pg.254 ]



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