Bromonitro compounds synthesis

Alkenes can be nitromeicurated (HgQ2/2 NaNOs/H20, 30 h, 25 Q and the products can be bromo-demercurated, giving bromonitro compounds. An alternative woik-up with base provides a valuable nitroalkene synthesis (Scheme 84). °... 

Olefin synthesis. Komblum et al. have described a new synthesis of tetrasubsti-tuted olehns from vicinal dinitro compounds. There are several methods for conversion of aliphatic and alicyclic nitro compounds into w c-dinitro compounds, the most useful of which is a procedure of Seigle and Hass. AnitroparaHin is converted into the lithium salt (I) by treatment with lithium methoxide and this is then treated with bromine to form a bromonitro compound (2). Reaclion of (2) with a second equivalent of the nitro-... 

Denitrocyclization strategy is potentially useful for the synthesis of a wide range of tricyclic compounds. The approach was found useful for the synthesis of thienobenzothiazole 339 and 343 starting from the corresponding bromonitro-thiophenes 336 and 340, respectively (Scheme 52) (68MI2, 72IJS(B)109). 

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