Synthesis of Nitroaromatic Compounds via Three-Component Ring Transformations

1-Methyl-3,5-dinitro-2-pyridone serves as an excellent substrate for nucleophilic-type ring transformation because of the electron deficiency and presence of a good leaving group. In this review, we focus on the three-component ring transformation (TCRT) of dinitropyridone involving a ketone and a nitrogen source. When dinitropyridone is allowed to react with a ketone in the presence of ammonia, TCRT proceeds to afford nitropyridines that are not easily produced by alternative procedures. Ammonium acetate can be used as a nitrogen source instead of ammonia to undergo the TCRT, leading to nitroanilines in addition to nitropyridines. In these reactions, dinitropyridone serves as a safe synthetic equivalent of unstable nitromalonaldehyde.

Catalyzed ring transformation of cyclic N-aryl-azadiperoxides with participation of α,ω-dithiols

Co(OAc)2-catalyzed ring transformation reaction of 10-aryl-7,8,12,13-tetraoxa-10-azaspiro[5.7]tridecanes with α,ω-dithiols giving 3-aryl-1,5,3-dithiazacyclanes was studied.

Synthesis of Decaarylanthracene with Nine Different Substituents

A synthesis of decaarylanthracene with nine different substituents has been accomplished by a coupling/ring-transformation strategy. The oxidation of tetraarylthiophenes with four different substituents to the corresponding thiophene <i>S</i>-oxides, and a [4+2] cycloaddition with a double benzyne precursor afforded a multiply arylated naphthalene derivative. Subsequently, the naphthalene derivative was converted into a naphthalyne, and then a [4+2] cycloaddition of another thiophene <i>S</i>-oxide provided decaarylanthracenes with nine different aryl groups.

Synthesis of Decaarylanthracene with Nine Different Substituents

A synthesis of decaarylanthracene with nine different substituents has been accomplished by a coupling/ring-transformation strategy. The oxidation of tetraarylthiophenes with four different substituents to the corresponding thiophene <i>S</i>-oxides, and a [4+2] cycloaddition with a double benzyne precursor afforded a multiply arylated naphthalene derivative. Subsequently, the naphthalene derivative was converted into a naphthalyne, and then a [4+2] cycloaddition of another thiophene <i>S</i>-oxide provided decaarylanthracenes with nine different aryl groups.