103095-60-9Relevant academic research and scientific papers
Experiments on the Chaperon effect in the nitration of aromatics
Strazzolini, Paolo,Giumanini, Angelo G.,Runcio, Antonio,Scuccato, Massimo
, p. 952 - 958 (1998)
A nitro group may be effectively delivered to the ortho position of alkylbenzenes, provided that a suitable chaperon function is located in α- position and a dilute of HNO3 in CH2Cl2 is used. The carbonyl function of an aldehyde or ketone is the best choice, but a carboxyl, alkoxycarbonyl, and amide groups all work well. The ether function showed a less pronounced ortho orientation effect, whereas the hydroxyl group was too prone to oxidation. Side reactions were minimal under the conditions employed. A para chaperon effect was seemingly at work in the CH2Cl2 nitration of benzenepropanenitrile. All the results were compared with the corresponding classical nitration in H2SO4.
Ozone-mediated nitration of phenylalkyl ethers, phenylacetic esters, and related compounds with nitrogen dioxide. the highest ortho substitution observed in the electrophilic nitration of arenes
Suzuki, Hitomi,Takeuchi, Toyomi,Mori, Tadashi
, p. 5944 - 5947 (2007/10/03)
By the combined action of ozonized oxygen and nitrogen dioxide (the kyodai-nitration), the title compounds were smoothly nitrated in dichloromethane at subzero degrees with hiigh ortho positional selectivity. Although the conventional nitration of phenylacetic acid and esters mainly produces m- and p-nitro derivatives, the present nitration offers a simple high-yield synthesis of o-nitro derivatives which are important as precursor in organic synthesis. The proportions of the ortho isomer in the nitration products from methyl 2-phenylethyl ether and methyl phenylacetate were 71 and 88%, respectively, the latter value being the highest ortho isomer proportion so far observed in the electrophilic aromatic nitration. The observed high ortho selectivity has been rationalized in terms of radical cation intermediate and six-membered cyclic transition state.
