Tris(tetrabutylammonium) tris(nitrato-κ2 O,O′)tetrakis(thiocyanato-κN)thorium(IV)

The title compound, (C16H36N)3[Th(NCS)4(NO3)3], was obtained from the reaction of Th(NO3)4·5H2O with (Bu4N)(NCS). The ThIV atom is in a ten-coordinate environment of irregular geometry, being bound to the N atoms of the four thiocyanate ions and to three bidentate nitrate ions. The average Th—N and Th—O bond lengths are 2.481 (10) and 2.57 (3) Å, respectively.

The title compound, (C 16 H 36 N) 3 [Th(NCS) 4 (NO 3 ) 3 ], was obtained from the reaction of Th(NO 3 ) 4 Á5H 2 O with (Bu 4 N)(NCS). The Th IV atom is in a ten-coordinate environment of irregular geometry, being bound to the N atoms of the four thiocyanate ions and to three bidentate nitrate ions. The average Th-N and Th-O bond lengths are 2.481 (10) and 2.57 (3) Å , respectively.
The family of actinide thiocyanate derivatives is of potential interest for the comprehensive coordination chemistry of f-block elements with applications in selective reactivity. In comparison with parent lanthanide elements, actinide thiocyanate derivatives have been poorly studied in the past. In the title complex [NBu 4 ] 3 [Th(NCS) 4 (NO 3 ) 3 ], (I), the metal cation is 10-coordinated with three bidentate nitrate ions and four N-bonded thiocyanates. The coordination polyhedron is quite irregular, but, if the three nitrate ions are considered as single donors, it may be noted that the four N atoms of the thiocyanate ions and the atom N5 of the nitrate ion bound through O1 and O2 define a mean plane with an r.m.s. deviation of 0.318 Å, which contains the Th atom, displaced by 0.003 (3)

Experimental
Caution! With thorium being a radioactive and chemically toxic element, thorium-containing samples must be handled with suitable care and protection. All starting materials used in these synthetic reactions are available commercially and were used as obtained from the supplier. Th(NO 3 ) 4 .5H 2 O (0.474 mmol, 0.27 g) was dissolved in hot ethanol (25 ml). After complete dissolution, tetrabutylammonium thiocyanate, C 17 H 36 N 2 S, (5 mmol, 1.5 g) was added directly to the solution in a ratio

Refinement
Restraints were applied for five bond lengths in the tetrabutylammonium cations. The H atoms were introduced at calculated positions as riding atoms, with C-H bond lengths of 0.97 Å (CH 2 ) or 0.96 Å (CH 3 ), and with U iso (H) values of 1.2 (CH 2 ) or 1.5 (CH 3 ) times U eq (C).

Special details
Experimental. crystal-to-detector distance 30 mm Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating Rfactors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.