Butyroyl chloride

The scope of the Negishi-coupling is not limited to aryl and vinyl halides and sometimes acyl chlorides might also be converted to ketones by this protocol. The 2,3-dihalopyrrole derivative shown in 6.22. was converted into its 2-lithio derivative by selective lithium-halogen exchange at -78 °C. Addition of zinc chloride effected the formation of the appropriate pyrrolylzinc chloride, which was coupled with a functionalised butyroyl chloride in the presence of tetrakis(triphenylphosphino)palladium and furnished the expected 2-acylpyrrole in 61% yield.27... 

Tridimensional Y and BEA zeolites are also utilized as efficient catalysts in the acylation of tetralin with acyl chlorides. By using octanoyl chloride and butyroyl chloride in the presence of zeolite Y(40), good yields in the acylation products are achieved (83% and 77% yield, respectively, after 8 h), whereas acetyl chloride (AC) leads only to less than 20% yield of the two isomeric ketones 1 and 2 (1/2 = 7.5) (Scheme 4.2). This trend is correlated to the influence of the chain length of the acylating agent on the efficiency of Friedel-Crafts acylation over zeolite catalysts previously discovered and rationalized. The lower activity of zeolite Y(40) with AC is related to the strong adsorption of organic species, either acetic acid (AAC) or acetyl tetralin. 

Butyroyl chloride was utilized in the acylation of thiophene in the presence of zeolite Y with the aim of studying the nature and effect of the catalytic acid sites. The reaction is performed in chlorobenzene at... 

The same catalyst gives excellent synthetic results in the acylation of thiophene with different acyl chlorides. For example, 2-butyroylthio-phene is easily and quantitatively produced from the acylation of thiophene with butyroyl chloride at 100°C after 7 h. Higher homologs lead to identical results (Scheme 4.9). 

BUTYROYL CHLORIDE (141-75-3) Forms explosive mixture with air (flash point <70°F/<21°C). Slowly reacts with moist air, water, steam, and alcohols, forming hydrogen chloride and phosgene gas. Violent reaction with strong oxidizers, strong bases. Corrodes metals in the presence of moisture. May accumulate static electrical charges may cause ignition of its vapors. 

The acylation of thiophene (T) with butyroyl chloride (BC) at 100°C in presence of HY (Si/Al =15) in liquid phase, with chlorobenzene used as solvent... 

The initial rates of disappearance of thiophene were determined at different initial concentrations of each of the reactants (from 0.05 to 1 mol.l ) while the initial concentration of the other was kept constant (0.4 mol.l- for butyroyl chloride and 0.2 mol.l for thiophene). 

Figures 1 and 2 show the evolution of the initial reaction rate with the initial concentration of thiophene and butyroyl chloride respectively. The behaviour is similar for these two reactants. The initial acylation rate increases, passes through a maximum, and then decreases. We can note that the decrease is slightly more important with thiophene than with chloride.

These kinetic observations indicate a competitive activation of the two reactants, leading to an inhibiting effect at high concentrations. The results can be interpreted in terms of a Langmuir - Hinshelwood mechanism for which the surface reaction takes place between thiophene and butyroyl chloride both adsorbed on identical active sites. 

From these diagrams, the ratio of adsorption coefficients of thiophene and butyroyl chloride can be calculated Xj / XbC = 1-5... 

This values indicates that, thiophene is more adsorbed than butyroyl chloride. 

Dealuminated HY zeolites have been shown to be efficient catalysts for the selective preparation of 2-acyl thiophenes in the reaction nf thiophene with various acyl chlorides. The acylation reaction of thiophene with butyroyl chloride over HY (Si/Al =15) zeolite, in chlorobenzene as solvent, follows a Langmuir-Hinshelwood kinetic law, which involves the adsorption of the two reactants on identical sites of the catalyst surface. ... 

Full details are also available of the structure elucidation of elaeokanines A-E, and elaeokanidines A-C, the leaf alkaloids of E. kaniensis Schltr. further, the structures of elaeokanines A-C have been confirmed by synthesis. The reaction of the diazoketone prepared from butyroyl chloride and diazomethane with pyrrole in the presence of copper powder gave the ketone (9), which was hydrogenated to the basic pyrrolidine ketone (10). Michael addition of ethyl acrylate... 

This approach to the synthesis of the 4-dimethylaminobutyrate ester (50, R = (CH2)3NMe2) involved initial reaction of pristinamycin 11 with 4-chloro-butyroyl chloride in the presence of dimethylaniline yielding the 4-chlorobutyr-ate ester (50, R = (CH2)3C1, 32%), followed by reaction with dimethylamine in methanol at 40 °C. This did indeed provide the required semi-synthetic pristinamycin 11 derivative (50, R = (CH2)3NMe2), which was soluble in water as its hydrochloride salt, but the yield was low (5%). The use of alternative secondary amines in the final reaction did not result in any improvement in the yield. 

Butyroyl chloride. See Butyryl chloride Butyroyl tri hexyl citrate CAS 82469-79-2... 

Synonyms Butanoyl chloride Butyric acid chloride Butyric chloride Butyroyl chloride N-Butyryl chloride... 

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