A novel and versatile entry to asymmetrically substituted pyrazines.
A novel and convenient procedure for the synthesis of asymmetrically tri- and tetrasubstituted pyrazines starting from para-methoxybenzyl-protected 3,5-dichloro-2(1H)-pyrazinones was elaborated. The key step is the conversion of the intermediate para-methoxybenzyl-protected thiopyrazinone upon treatment with MeI/I(2), into a pyrazine, rendering the chlorine in the C5-position susceptible to substitution. This approach entails the orthogonal introduction of the four substituents of the pyrazine scaffold. The application of microwave irradiation during different steps of the sequence has been shown to be highly valuable for speeding up reactions.
Mehta
Vaibhav Pravinchandra
VP
Laboratory for Organic and Microwave-Assisted Chemistry, Biomolecular Architecture, Department of Chemistry, University of Leuven (K. U. Leuven), Celestijnenlaan 200F, B-3001, Leuven, Belgium.
Sharma
Anuj
A
Hecke
Kristof Van
KV
Meervelt
Luc Van
LV
Eycken
Erik Van der
EV
D011719:Pyrazines / Q000138:chemical synthesis* / Q000737:chemistry
D011719:Pyrazines