Ortho-nitrobenzyl Chloride

Ortho-nitrobenzyl chloride was prepared in 1883 by Abelli, together with the meta-compound, by the reaction of concentrated nitric acid on benzyl chloride. It may also be obtained, according to Haussermann and Beek, by the action of chlorine at 130° to 140° C. on a mixture of 2 parts of o-nitrotoluene and i part sulphur. 

According to Lindemann, it was used by the French during the war mixed with / -nitro benzyl chloride under the name of Cedenite  

With potassium iodide it is easily converted into o-nitrobenzyl iodide, and an alcoholic solution of potassium cyanide converts it into o-nitrobenzyl cyanide. Potassium permanganate oxidises it to o-nitrobenzoic acid. 

Xylyl bromide was prepared in 1882 by Radziszevsky. It was used for the first time as a war gas in January, 1915, but its use was abandoned towards the end of the war because of the ease with which it was dealt with by the ordinary carbon filters and of the inconvenience caused by its attack on iron containers. It is also known as T-Staff.  

Xylyl bromide may be easily prepared by the reaction of bromine on commercial xylol. This reaction is carried out either by heating the xylol to 115° C. or by exposing the reaction-mass to the action of a light source rich in ultra-violet radiations and keeping the temperature at 50° to 60° C.  

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A study of alkylations with a group of substituted benzyl halides and a range of Friedel-Crafts catalysts has provided insight into the trends in selectivity and orientation that accompany changes in both the alkyl group and the catalysts. There is a marked increase in substrate selectivity on going from / -nitrobenzyl chloride to /i-methoxybenzyl chloride. For example, with titanium tetrachloride as the catalyst, Aitoi Abenz increases from 2.5 to 97. This increase in substrate selectivity is accompanied by an increasing preference for para substitution. With /i-nitrobenzyl chloride, the ortho para ratio is 2 1 (the... 

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