Dicarbonyl Compounds, frames

Since cyclohexenes can also be made by the Diels-Alder reaction (frames 5-8) we have access to a wide range of 1,6-dicarbonyl compounds. How about TM 196 ... 

Analysis Our methods for making 1,2-dioxygenated compounds (frames 154-157) involve reductive linking of a dicarbonyl compound ... 

Analysis This is a 1,6-dicarbonyl compound so a recormection is called for. The next obvious series (frames 36-8) of discormections ends up at 382B - not an easy compound to make. Where could we put a carbonyl group in 382A to allow some more helpfiil discormections ... 

Analysis Taking the heterocychc part first, we can remove the two heteroatoms as hydroxylamine (the approach of frames 258-261) to give us a 1,3-dicarbonyl compound. 

It is rather surprising to find a compound with only one activating group among the others, but the nitro group is very electron-withdrawing so that the pK of nitro-methane is 10 it is even more acidic than most dicarbonyl compounds. Go to frame 268. 

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