an efficient and green procedure for the preparation of 5-chloropyrazine- 2-carboxylic acid from methyl 5-chloropyrazine-2-carboxylic acid ester using LiOH with the evident advantages of very easy operations, environmentally benign conditions and high yield of the product. It is a very green and easy transformation for no organic solvents were used during the whole reaction and separation procedure to obtain the high yield