Iodo-4-Nitrobenzene

The electrochemically induced S l reaction of haloarenes with uracil anion (177) in DMSO gave 5-aryl uracils 178 in 30-55% yields (equation 123)227. Thus, good yields of the 5-aryl uracils were obtained in the reaction with 4-bromobenzophenone (55%), 4-chlorobenzonitrile (50%) and l-iodo-4-nitrobenzene (55%). With l-iodo-2-trifluoromethylbenzene (and with phthalonitrile as a redox catalysis), 30% of the 5-aryl uracil was formed. 

Examples of the reaction arc given in Table 12. Similar yields are obtained when l-(difluoro-iodo)-4-nitrobenzene is used as the fluorinating agent. Only catalytic amounts of the reagent are required if an electrochemical synthesis is used where the (difluoroiodo)arene serves as an in-cell mediator for the fluorination of the dithiolane. 

Palladium-catalyzed reactions can be used to connect the terminal end of an alkyne and aromatic iodide, as shown in the reaction below. They are useful in industry and are widely employed in the academic arena. The experiment presented here was adapted from an article by Goodwin, Hurst, and Ross. The mechanism shown is for the coupling of l-iodo-4-nitrobenzene with 1-pentyne. Small amounts of a dimer obtained from the coupling of the 1-alkynes are also formed in these... 

MHz NMR spectrum of the product of 1-iodo-4-nitrobenzene and 1-hexyne. A trace of a dimer, 5,7-dodecadiyne, formed from 1-hexyne is observed at about 0.9 ppm (3H), 1.4 ppm (4H), and 2.2 ppm (2H) in the NMR spectrum. Traces of other impurities are also found in the spectrum. CHClg appears at about 7.25 ppm. 

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