Toluene, o-iodo

Reaction Procedure (Scheme 2.3) To a 100 mL stainless steel autoclave, o-iodo derivative (0.5 mmol), amine (0.7 mmol), 10% Pd/C (2.5 mol%), toluene (7 mL) and DABCO (1.5 mmol) were added. The autoclave was closed, purged three times with carbon monoxide, pressurized with 90 psi of CO and then heated at 120 °C for 2 h. The reactor was cooled to room temperature and the remaining CO gas was carefully vented and the reactor was opened. The reactor vessel was thoroughly washed with ethyl acetate (2x10 mL) to remove any traces of product and catalyst if present. The catalyst was filtered and the reaction mixture was evaporated under vacuum. The residue obtained was purified by column chromatography (petroleum ether-ethyl acetate, 95 5) to afford the desired product. 

The SrjjI reaction of o-iodo and o-bromo-benzoate salts with CHjCOMe ion affords the substitution product ca. 78% yield), which upon acid treatment with toluene p-sulphonic acid gives the corresponding isocoumarin 15 (90%) (Scheme 4). Benzazepines 16 can be produced upon ammonium acetate treatment of the substitution compound obtained in the reaction of (o-iodophenyl) acetic acid derivatives with enolate ions from ketones ( CHjCOR, R = Me, i-Pr, t-Bu 50, 60, and 56%, respectively) (Scheme 5)." ... 

Methyl a-D-mannopyranoside was treated in succession with p-toluene-sulfonyl chloride, carbonyl chloride, and benzoyl chloride, and, without isolating the intermediates, there was obtained in 37% yield methyl 4-0-l enzoyl-2,3-O-carbony 1-6-0-(p-tolylsulfonyl ) -D-mannoside. The tos-yloxyl group of the latter was replaced by iodine, and hydrogenation of the 6-iodo derivative in the presence of a nickel boride catalyst gave methyl 4-0-benzoyl-2,3-0-carbonyl-6-deoxy- -D-mannoside. Treatment of the latter with hydrogen bromide in acetic acid gave crystalline 4-0-benzoyl-2,3-0-carbonyl-6-deoxy-a-D-mannosyl bromide (8) (16). The... 

Halo and nitro groups on the benzene ring are unaffected by the oxidation of an alkyl group, o- and p-Nitro-, o-chloro-, and p-iodo-benzoic acids have been made from the substituted toluenes. 

The stereoselective introduction of an ethynyl group in various flve- and six-membered iodohydrins has also been developed by the same group (O Scheme 37) [60]. Treatment of 3 -ethynyldimethylsilyl 2-deoxy-2-iodo-D-mannopyranoside 142 with Et3B and TBAF in toluene furnished the methyl 2-deoxy-2-C-ethynyl-4,6-0-benzylidene-a-D-mannopyranoside 144 in 85% yield. However, a similar reaction of 3-iodo-D-ribosyl substrate 143 having the [2-(trimethylsilyl) ethynyl]dimethylsilyl at C-5 gave the desired product 5-0-acetyl-3-deoxy-3-C-ethynyl-l,2-0-(l-methyl ethylidene)-a -D-xylofuranose, in which the ethynyl group was introduced at the y-cis position to the 5 -hydroxyl, in only 31% yield. This may be explained by an unfavored 6-exo radical cyclization. 

Halogen substituted toluenes are readily converted into nitriles because electron-withdrawing substituents enhance the reactivity of such compounds in the ammoxidation reaction. The fluoro-, chloro-, bromo-, and iodo-substituted toluenes [e. g. 41,74-76] can, therefore, be converted to the corresponding nitriles. Whereas the conversion rate of /7-halotoluenes (over vanadium phosphate catalysts [41,75]) is nearly independent of the nature of the halogen substituent, the selectivity decreases in the sequence p-Cl > /7-Br >> p-l. Ammoxidation of isomeric chloro-toluenes results in different conversion p o > m) and selectivity p > o > m) sequences [41,75,76]. 

The unsaturated nucleoside (53) has been prepared in good yield by electrochemical elimination from either the 2 -bromo-arabino- or the 3-bromo-xylo-nucleoside indicated in Scheme 14 however, the electrolyte can control the product obtained, for whereas 2-bromo-2 -deoxy-3, 5-di-O-propanoyl-uracil gave the 2, 3-unsaturated nucleoside in presence of tetraethylammonium toluene-p-sulphonate in methanol, with sodium acetate a mixture of products was obtained 3-deoxy-3-iodo-adenosine yielded 3-deoxy-adenosine (cordycepin) besides the 2, 3-unsaturated nucleoside.1-Acetyl-glycenose derivatives have been condensed with purine and pyrimidine derivatives in presence of antimony... 

Because of the inefficiency of the nitrodeiodination reaction and the faster rate of nitration of o-xylene relative to 4-iodo-o-xylene, I2 cannot be used as a catalyst to alter the substitution pattern in the nitration of o-xylene. ° Mononitration of m-xylene with HNO3 in a liquid mixture of m-benzenedisulphonic acid and phosphoric acid gives excellent yields and a 4-nitro-isomer content higher than that obtained by the usual method. In a typical experiment, the yield was 96% and the 4- to 2-isomer ratio ca. 7.5. A white product obtained during the nitration of toluene has been identified as (46). The catalytic para-nitration of substituted benzenes, especially toluene, has been reviewed, but in Japanese. 

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