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Alumina coated with potassium fluoride promotes smooth N-alkylation of carboxamides, lactams, and other N-heterocycles with alkyl halides or dialkyl sulfate under mild conditions.

Comparison of KF and NaF impregnated on active alumina shows that the formation of strong base by fluoride reaction with alumina cannot totally explain the extremely high reactivity of KF-alumina as a heterogeneous base for catalytic as well as non-catalytic reactions. At least three mechanisms apparently give rise to the high basicity.

Relative FABMS peak-intensities of the cluster ions between a set of permethylated aldopyranoses and potassium ion provide a lose relation with relative FABMS/MS area-intensities of the corresponding cluster ions between a set of methyl aldopyranosides and potassium ion.

1,1,2,2-Tetraacylcyclopropanes (1a, 1b) were rearranged into nine-membered enol lactones (2a, 2b) by tertiary amines, while primary arylamines brought about retro-Mannich reaction to give bisdimedone (4) and Schiff base.

By using 1H-NMR relaxation technique, an ordering of complexation ability for a series of permethylated aldopyranoses with metal cations in solution has been determined, which is identical with that of the peak-intensity for the 1:1 adduct ions by FAB mass spectrometry.

The relative FABMS intensities of the cluster ions between permethylated monosaccharides and glycine methyl ester hydrochloride strongly suggest the configuration effect of the OCH3groups, reflecting the relative stabilities of the cluster ions in gas phase.

The carbonyl carbon-14 kinetic isotope effect and substituent effects were determined for the reaction of MeMgI with benzophenone. The observed large carbon isotope effect (14k⁄12k=1.056) together with the large steric effect on reactivity introduced by o-substituents on benzophenone indicated that the C–C bond formation is the rate-determining step of the Grignard reaction.

The carbon-14 kinetic isotope effect (KIE) was determined for the reduction of benzophenone-carbonyl-14Cwith lithium isopropoxide in THF at 25 °C. The observed KIE (12k⁄14k=1.045) suggested that there is considerable bonding change at the carbonyl carbon in the transition state. This is the first example of carbon KIE in a reaction which proceeds via initial electron transfer followed by a slow radical process.

The reactions of allyl magnesium bromide and crotyl magnesium bromide with benzophenone were determined to proceed via a rate-determining electron transfer mechanism by means of the isotope effect and substituent effect technique.

The isomerisation of a cyclopropylmethyl radical into a homoallyl radical is discussed on the basis of the reduction product of the titled compounds along with recent reports.

Correlation between the result on the reaction of ketones with zinc dust in acetic acid and their polarographic half-wave reduction potential in organic solvents is described.

The 1 : 1 adduct ion formation between a series of per-O-acetylated aldopyranoses (family 1) or N-butylated glycosylamines (family 2) and an organic/metallic cation (n-C8H17NH3+/K+or Li+) has been examined using quantitative FAB mass Spectrometry. The per-O-acetyl modifications dramatically lead to negated selectivity of the carbohydrates toward the cation which has been clearly observed in per-O-methyl modifications. On the other hand, the mono-N-butyl modifications provide a similar selectivity pattern to mono-O-methyl ones. These results are understood on the basis of electronic and structural considerations.

The reaction of tetramethylbenzenedicarbonitriles and tetramethylbenzonitriles with fuming nitric acid (d=1.5) has been investigated at room temperature in the dark. 2,4,5,6-Tetramethylbenzene-1,3-dicarbonitrile and 2,3,5,6-tetramethylbenzene-1,4-dicarbonitrile gave, after aqueous work-up, 4-cyano-5,6,7-trimethyl- and 5-cyano-4,6,7-trimethylphthalides, respectively, in high yields, while 3,4,5,6-tetramethylbenzene-1,2-dicarbo-nitrile produced appreciable amounts of two cyanonitro-3-cyclohexen-1-ones in addition to 7-cyano-4,5,6-trimethylphthalide. Similarly, 2,3,4,6- and 2,3,5,6-tetramethylbenzonitriles afforded 4-nitro-5,6,7-trimethyl- and 5-nitro-4,6,7-trimethylphthalides, respectively, along with the expected nitro compounds. In contrast, 2,3,4,5-tetramethylbenzonitrile underwent normal nitration, giving 6-nitro derivative as the sole product. The phthalide formation was found to proceed through 1,3-dihydroisobenzofuran-1-imines presumably derived from the initially formed o-cyanobenzyl nitrates. The reaction appears to provide potential utility in the synthesis of some substituted phthalides and 1,3-dihydroisobenzofuran-1-imines.

A new composite reagent, a combination of lead fluoride (PbF2) and a small amount of sodium salt (NaX, X = F, Br etc.) was found to be useful for facilitating heterogeneous fluorination of substituted benzyl halides in acetonitrile.

The monocyclopropanation of 4-pyrones with dimethyloxosulfonium methylide, using a dimethyl sulfoxide hexamethylphosphoric triamide medium in place of neat dimethyl sulfoxide, gave homo-4-pyrone derivatives, which were then rearranged into the 2-furylacetone derivatives, along with hydra ted triketones or the dehydrated naphtho[2,1-b]furan derivative, by means of strong acid catalysis at room temperature.

Combined use of alumina and ultrasound facilitates the synthesis of α-aminonitriles under solid–liquid two phase conditions from carbonyl compounds, salts of amines and potassium cyanide in organic solvents.

Combined use of alumina, a trace of water, and ultrasound greatly accelerated a solid–liquid two-phase nucleophilic substitution by cyanide ion in nonpolar organic solvents. The efficiency under the optimum conditions were compared with that of phase transfer catalysts such as 18-crown-6.

Arylmalononitriles were prepared from the corresponding benzoyl chlorides by three reaction steps . Treatment of the starting substances with cyanotrimethylsilane in the presence of pyridine gave dicyanotrimethylsiloxymethylbenzenes, which were transformed into chlorodicyanomethylbenzenes with POCl3-pyridine in the second step. Finally, reduction of chlorodicyanomethylbenzenes with Zn–CH3CO2H afforded arylmalononitriles.

Vinylcyclopropane derivatives could be synthesized with one-pot procedure from α,β-unsaturated thione (chromothione) derivatives by dimethyloxosulfonium methylide. Extremely facile addition of tetracyanoethylene with 4-methylene-4H-homochromenes gave dihydrobenzoxazepine derivatives. The reaction may be well interpreted with the homoaromatic stabilization of the cationic part in a zwitterionic intermediate which would be formed at the rate-determining step.

Polyalkylbenzyl thiocyanates, upon irradiation in acetic acid, readily undergo reversible photoisomerization, giving an equilibrium mixture composed mostly of the corresponding isothiocyanates. Several new bis- and tris(isothiocyanatomethyl)polymethylbenzenes have been prepared by utilizing the photoinduced multiple thiocyanate isomerization.