Process for the preparation of heteroaryl-zinc halides
AssigneeZambon Group S.p.A.
InventorsMario Fantucci, Francesco Santangelo
Life of this patent
Estimating the term…
Abstract
A process for the preparation of heteroaryl-zinc halides of the formula (II): Het—Zn—X, wherein Het is an optionally substituted 5 or 6 membered aromatic heterocyclic group with one or two heteroatoms selected among nitrogen, oxygen or sulphur; X is a chlorine, bromine or iodine atom; comprising metallation reaction of heteroarylhalide with metallic zinc optionally activated by washing with acids, is described. Compounds of the formula (II) are intermediates useful in the synthesis for the preparation of compounds endowed with pharmacological activity.
Claims13
A process for the preparation of heteroaryl-zinc halides of the formula
- Het—Zn—X (II)
- wherein
- Het is an optionally substituted 5 or 6 membered aromatic heterocyclic group with one or two heteroatoms selected from among nitrogen, oxygen or sulfur;
- and
- X is a chlorine, bromine or iodine atom;
- that consists essentially of the metallation reaction of a compound of formula
- Het—X (III)
- in which
- Het and X have the above reported meanings;
- characterized by the fact that the metallation reaction is carried out with metallic zinc dust, optionally activated by washing with acids.
A process for preparing heteroaryl-phenylalanines of the formula I
- wherein
- R is a hydrogen atom, a straight or branched C1-C4 alkyl group or benzyl group;
- Het is an optionally substituted 5 or 6 membered aromatic heterocyclic group containing one or two heteroatoms selected from the group consisting of nitrogen, oxygen and sulphur;
- said process comprising reacting a halo substituted compound of the formula III
- Het—X III
- wherein
- Het has the meaning above and X is selected from the group consisting of chlorine, bromine and iodine, with metallic zinc optionally activated with washing acids to generate Het—Zn—X and thereafter conducting a cross-coupling reaction to generate the compound of formula I.
Dependencies are inferred from the claim text.