Process for the preparation of dihydropyrrole derivatives

A mixture comprising a compound of formula I and a compound of formula IA

• wherein the mixture is enriched for the compound of formula I;
• or
• a mixture comprising a compound of formula III and a compound of formula IlIA
• wherein the mixture is enriched for the compound of formula III;
• or
• a mixture comprising a compound of formula IV and a compound of formula IVA
• wherein the mixture is enriched for the compound of formula IV;
• or
• a mixture comprising a compound of formula XXIII and a compound of formula XXIIIA
• wherein the mixture is enriched for the compound of formula XXIII;
• or
• a mixture comprising a compound of formula XXIV and a compound of formula XXIVA
• wherein the mixture is enriched for the compound of formula XXIV;
• and wherein
• R1 is chlorodifluoromethyl or trifluoromethyl;
• R2 is optionally substituted aryl or optionally substituted heteroaryl;
• P is phenyl, naphthyl, a 6-membered heteroaryl group containing one or two nitrogen atoms as ring members, or a 10-membered bicyclic heteroaryl group containing one or two nitrogen atoms as ring members, and wherein the phenyl, naphthyl and heteroaryl groups are optionally substituted;
• n is 0 or 1;
• Y is hydrogen or optionally substituted aryl,
• W is optionally substituted aryl;
• and
• Z is optionally substituted alkyl or optionally substituted arylalkylene.

A compound of formula V, or a salt or N-oxide thereof,

• a compound of formula VI, or a salt or N-oxide thereof,
• wherein
• R1 is chlorodifluoromethyl or trifluoromethyl;
• R2 is optionally substituted aryl or optionally substituted heteroaryl;
• n is 0 or 1;
• A3 and A4 are C—H, or one of A3 and A4 is C—H and the other is nitrogen;
• R5a is hydrogen;
• R5b is methyl;
• or R5a and R5b together form a —CH═CH—CH═CH— bridge;
• R is halogen, OH or C1-C15alkoxy;
• and
• XB is a leaving group.

A compound of formula XXIIIr, or a salt or N-oxide thereof,

• or
• a compound of formula XXIVr, or a salt or N-oxide thereof,
• wherein
• P is phenyl, naphthyl, a 6-membered heteroaryl group containing one or two nitrogen atoms as ring members, or a 10-membered bicyclic heteroaryl group containing one or two nitrogen atoms as ring members, and wherein the phenyl, naphthyl and heteroaryl groups are optionally substituted;
• R1 is chlorodifluoromethyl or trifluoromethyl;
• R2 is optionally substituted aryl or optionally substituted heteroaryl;
• W is hydrogen or optionally substituted aryl;
• Y is optionally substituted aryl;
• and
• Z is optionally substituted alkyl or optionally substituted arylalkylene.