Process for the preparation of 1-H-pyrrolidine-2,4-dione derivatives
The present invention relates to a novel process for the preparation of 1-H-pyrrolidine-2,4-dione derivatives and to novel intermediates and to a process for their preparation.
1. A compound of formula (X):
in which
A, B and the carbon atom to which they are bonded are saturated C 6 -cycloalkyl in which one ring member is replaced by oxygen, or
A, B and the carbon atom to which they are bonded are C 6 -cycloalkyl which is disubstituted by fluorine or monosubstituted by methoxy, or
A, B and the carbon atom to which they are bonded are C 6 -cycloalkyl which is substituted by an alkylenediyl group having with two non-directly adjacent oxygen atoms, which, with the carbon atom to which it is bonded, forms a further five-membered ring,
G is hydrogen (a) or
where R 2 is ethyl,
V is hydrogen (X-1) or COOR 8 (X-2),
where R 8 is methyl.