Di-n-butyl{4-hydroxy-N′-[(2-oxido-1-naphthyl-κO)methylene]benzohydrazidato-κ2 O,N′}tin(IV)

The deprotonated Schiff base ligand in the title compound, [Sn(C4H9)2(C18H12N2O3)], O,N,O′-chelates to the Sn atom, which is five-coordinated in a cis-C2NO2Sn trigonal-bipyramidal environment. The apical sites are occupied by the O atoms [O—Sn—O = 155.2 (2)°]. The hydroxy group is a hydrogen-bond donor to the two-coordinate N atom of an adjacent molecule, the hydrogen-bonding interaction giving rise to a helical chain running along the c axis. The carbon atoms of the butyl chains are equally disordered over two positions.

The deprotonated Schiff base ligand in the title compound, [Sn(C 4 H 9 ) 2 (C 18 H 12 N 2 O 3 )], O,N,O 0 -chelates to the Sn atom, which is five-coordinated in a cis-C 2 NO 2 Sn trigonal-bipyramidal environment. The apical sites are occupied by the O atoms  ]. The hydroxy group is a hydrogen-bond donor to the two-coordinate N atom of an adjacent molecule, the hydrogen-bonding interaction giving rise to a helical chain running along the c axis. The carbon atoms of the butyl chains are equally disordered over two positions.

Related literature
For the synthesis of the Schiff base, see: Cui et al. (2007).
The apical sites are occupied by the oxgen atoms  (2) °]. Both butyl chains are disordered over two positions in a 1:1 ratio.

Refinement
Hydrogen atoms were placed in calculated positions (C-H 0.93 to 0.97, O-H 0.84 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2 to 1.5U eq (C,O).
The carbon atoms of the butyl chains are disordered over two positions; the occupancy could not be refined, and was assumed to be 50:50. The 1,2-related carbon-carbon distances were restrained to 1.54±0.01Å and the 1,3-related ones to 2.51±0.01 Å. The displacement ellipsoids of the primed atoms were restrained to be similar to those of the unprimed ones; furthermore, the ADP's were restrained to be nearly isotropic.
The final difference Fourier map had a peak/hole in the vicinity of Sn1. Fig. 1. Anisotropic displacement ellipsoid plot (Barbour, 2001) of Sn(C 4 H 9 ) 2 (C 18 H 12 N 2 O 3 ) at the 50% probability level; hydrogen atoms are drawn as spheres of arbitrary radius. The disorder in the butyl chains is not shown.