Acetonitrile reaction

Conditions substrate (1.25 mmols), acetic anhydride (3.75 mmols), catalyst (15 mg), solvent (4 mL of acetonitrile), reaction temperature (80°C), reaction time (18 h). TOP (h ) = [mmols of transformed substrate] / [mmols of active phase x time]... 

Aromatic diazo compounds can be reduced in water via a radical process (Scheme 11.5).108 The reduction mechanism of arenediazo-nium salts by hydroquinone was studied in detail.109 Arenediazonium tetrafluoroborate salts undergo facile electron-transfer reactions with hydroquinone in aqueous phosphate-buffered solution containing the hydrogen donor solvent acetonitrile. Reaction rates are first order in a... 

Compound 79 reacts with 0(CH2)4 and NCMe in the presence of CFsSOsMe, like the iron complex 11 and the molybdenum and tungsten complexes 45 and 46, to give zwitterionic compounds [2-NO-2-PEt3-7-L-c/ow-2,l-CoCBioHio] [L = 0(CH2)4 (83), NCMe (84)]. Interestingly, the acetonitrile reaction gave in addition to 84 small amounts of the imine complex [7- N(Me) = C(H)Me -2-NO-2-PEt3-c/oio-2,l-CoCBioHio] (85), a product related to the iron and nickel compounds 34 and 78, respectively. The latter pair were the only products when 11 and 75, respectively, were... 

In a similar manner, coccinelline (99) and precoccinelline (100) have been synthesized from 2,6-lutidine (351) (336,450). Thus, treatment of the monolithium derivative (153) of 351 with P-bromopropionaldehyde dimethylacetal gave an acetal, which was converted to the keto acetal (412) by treatment with phenyllithium and acetonitrile. Reaction of 412 with ethylene glycol and p-toluenesulfonic acid followed by reduction with sodium-isoamyl alcohol gave the cw-piperidine (413). Hydrolysis of 413 with 5% HCl gave the tricyclic acetal (414) which was transformed to a separable 1 1 mixture of the ketones (415 and 416) by treatment with pyrrolidine-acetic acid. Reaction of ketone 416 with methyllithium followed by dehydration with thionyl chloride afforded the rather unstable olefin (417) which on catalytic hydrogenation over platinum oxide in methanol gave precoccinelline (100). Oxidation of 100 with m-chloroperbenzoic acid yielded coccinelline (99) (Scheme 52) (336,450). 

Reaction of 220 (R = H) with malononitrile leads directly to formation of the cyanopyridonocoumarin, whereas with p-nitrophenyl-acetonitrile reaction stops at the pyronocoumarin stage. 

A mixture of phenol 1 (10 mmol) and a,/ -unsaturated carboxylic derivative 2, 4 or ethyl acetoacetate 6 (15-20 mmol) supported on 1 g of solid acid support (by dissolving the mixture in 5 mL of diethyl ether followed by evaporation of the solvent) was exposed to microwave irradiation in a focused microwave reactor (Prolabo MX350). For isolation of the compounds, the solid support was removed by extraction with ethanol (for reactants 2 and 6) or acetonitrile (reactions of 4). After solvent evaporation, the products were purified by column chromatography on silica gel (hexane-ethyl acetate, 3 1). 

In contrast to compounds 10-16 SiO C framework), the X Si-silicates 17 and 18 contain a S1O5 framework. The latter compounds were obtained by reaction of Si(OMe)4 with two mole equivalents of the respective a-hydroxycarboxylic acid and one mole equivalent of 2-(dimethylamino)ethanol in boiling acetonitrile (reaction time 50 h yield 61 % (17) or 77 % (18)). Recrystalli2ation of 18 from dimethylformamide yielded the 18 DMF solvate which was structurally characterized by single-crystal X-ray diffraction [11]. As can be seen from Fig. 6, the coordination polyhedron surrounding the silicon atom of 18 is a distorted trigonal bipyramid (Berry distortion [8] 13.9 %), in which the carboxylate oxygen atoms occupy the axial sites. 

In contrast, when a larger tetracationic cyclophane ring was employed in another set of experiments, the formation of new [3]-catenanes was found to be more facile. ° The expanded ring was obtained by replacing the phenylene linker units in the normal tetracationic cyclophane with biphenylene units. This larger ring was found to form readily around two threaded crowns when the latter are present in the acetonitrile reaction mixture in several-fold excess. Both bis-p-phenylene-34-crown-lO and l,5-dinaphtho-38-crown-10 were successfully employed in separate reactions to produce the corresponding [3]-catenanes in 20 and 31% yields, respectively. 

For the preparation of the required 1 2 [Ru ligand 47] intermediate, a pro-tection-deprotection strategy was employed. This involved reaction of 47 with trimethyloxonium tetrafluoroborate to block one metal co-ordination site in 47 to yield 48. After co-ordination of one ruthenium ion, the remaining site was unblocked by reaction with DABCO in refluxing acetonitrile. Reaction of this 1 2 (metal ligand) product with a second metal ion was then carried out. 

The experimental rate constant for the isocyanomethane (methyl isocyanide) to propanenitrile (acetonitrile) reaction is 3.6 x 10 s" at 298 K [142]. This compares astonishingly well with the value of 1.4 x 10 in Table 5.11, calculated from the G2 value of AG the calculated rate constant is only a factor of three too small (using G2 with A// gives a rate constant too small by a factor of ten). The CBS-Q... 

All pure alkynyliodonium species are microcrystalline solids. Their solubility is limited to non-nucleophilic polar solvents. They are insoluble in hydrocarbon, aromatic, ether, and other nonpolar solvents. They tend to decompose in methanol and ethanol as well as in dimethyl sulfoxide (DMSO), dimethylformamide (DMF), etc. With the exception of the parent ethynyliodonium salt they are also insoluble in water. The best solvent seems to be acetonitrile. Reactions may also be carried out under initially heterogeneous conditions in solvents like CH2CI2, CHCI3 where the mixture becomes homogeneous as the reaction proceeds. 

The rates of reaction of copper, zinc and uranium with dinitrogen tetroxide are greatly increased in the presence of acetonitrile Reactions of this type lead to the formation of acetonitrile complexes of the corresponding nitrate, which may loose coordinated acetonitrile by pumping in vacvo or heating. Reactions in such mixed acceptor solvent-donor solvent systems may provide unusual solvent properties and it is desirable that such systems should be investigated in considerable detail. 

Boron.—Boron-Hydrogen Compounds. Theoretical calculations have been made of likely sites for electrophilic and nucleophilic attack in a number of boranes and related anions. Electrophilic benzoylation of PioHjo " to form [2-BioH,COPh] follows simple second-order kinetics in acetonitrile. Reaction is inhibited by acid, and a kinetic analysis suggests that it is due to conversion of [BjoHioP" into the unreactive conjugate acid with K = 4.6moldm. The reaction of... 

Compared to the production of ACN+, the formation of the radical anion ACN- by photoinduced electron transfer has seldom been mentioned in the Hterature. Davidson has carried out irradiation of ACN in the presence of tertiary amines such as N,N-dimethylanihne and triethylamine in benzene and acetonitrile. Reaction in benzene affords 1 in the cisoid/transoid ratio of 1.0. On the other hand, in acetonitrile dsoid-l was formed, as well as acenaphthene (ACE), without affording transoid-l. Interpretation for the solvent-dependent product distribution is that the Tj state of ACN, produced from interaction... 

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