Bromoarylation of Methyl 2-Chloroacrylate under Meerwein Conditions for the Synthesis of Substituted 3-Hydroxythiophenes

Methyl 3-aryl-2-bromo-2-chloropropanoates can be prepared by Meerwein reaction from methyl 2-chloroacrylate and various arenediazonium salts under copper(II) bromide catalysis. The resulting readily available compounds were used as starting materials in reactions with substituted methanethiols for the construction of substituted 3-hydroxythiophenes which have not yet been accessible by other routes. Structural variety of the obtained 2-substituted 5-aryl-3-hydroxythiophenes has been achieved due to a wide range of available starting materials, including both anilines and thiols.

Application of the Meerwein reaction of 1,4-benzoquinone to a metal-free synthesis of benzofuropyridine analogues

Several new heterocyclic systems based on a hydroxybenzofuro[2,3-b]pyridine building block were prepared. This benzofuropyridine is easily available from the Meerwein reaction of benzoquinone and a heterocyclic diazonium salt, followed by reduction and cyclization. Electrophilic substitution and further condensations give polycyclic systems, including oxazolo- and chromeno-fused analogues.

A Three-Step Synthesis of 1,7-Diazaperylene and Derivatives

Abstract1,7-Diazaperylene and various derivatives were synthesised in an upscaleable route from 1,5-diaminoanthraquinone and its Meerwein­ reaction with acrylonitrile and subsequent cyclisation with ammonia. The application of tert-butyl alcohol as the solvent led to a significant improvement in the Meerwein reaction.