| abstract |
The present invention relates to processes for the enantio-selective preparation of spyrrolidine derivatives useful in the manufacture of pesticidally active compounds, as well as to intermedates in the processes. The processes include those comprising(a-i) reacting a compound of formula IawhereinP is alkyl, aryl or heteroaryl, each optionally substituted, wherein the heteroaryl is connected at P via a ring carbon atom;R<sup>1</sup> is chlorodifluoromethyl or trifluoromethyl;R<sup>2</sup> is aryl or heteroaryl, each optionally substituted;with a source of cyanide in the presence a chiral catalyst to give a compound of formula IIawherein P, R<sup>1</sup> and R<sup>2</sup> are as defined for the compound of formula Ia; and(a-ii) oxidising the compound of formula IIa with a peroxy acid, or peroxide in the presence of an acid to give a compound of formula VIwherein R<sup>1</sup> and R<sup>2</sup> are as defined for the compound of formula Ia. |