-KAPPA-C-2,3-KAPPA-C-2,4-KAPPA-C-2-BIS-MU(3)-OXO-1 /3/4-KAPPA-O-3-TETRAKIS-[MU-(2-PYRIDINECARBOXYLATO O-2,O'/4-KAPPA-O-1-KAPPA-O-2,O'/4-KAPPA-O-TETRATIN HYDRATE/

The unit cell of the title compound, bis[1,1,3,3-tetrabutyl-1,3-bis(pi colinato N-oxide)distannoxane] hydrate, [Sn-4(O)(2)(C4H9)(8) (C6H4NO3) (4)]. H2O, contains two independent centrosymmetric dicarboxylatotetra organodistannoxane dimers, one of which is hydrogen bonded to two wate r molecules. Both dimers possess a planar Sn2O2 core unit, the O atoms of which are covalently bonded to two [dibutyl(picolinato N-oxide)tin ] units. The endocyclic Sn atoms (of the Sn2O2 core units) are six-coo rdinate in C2SnO4 skew-trapezoidal bipyramidal environments whereas th e exocyclic Sn atoms (of the [dibutyl(picolinalo N-oxide)tin] units) a re seven-coordinate in trans-C2SnO5 pentagonal bipyramidal environment s.