STEREOCHEMISTRY OF POLYNUCLEAR COMPOUNDS OF MAIN GROUP ELEMENTS .11. DIMETHYL(METHYLTHIOL)ALUMINUM, [(CH3)2ALSCH3]N, A NEW TYPE OF STEREOCHEMISTRY FOR AN ORGANOALUMINUM COMPOUND

The crystal structure of dimethyl(methylthiol)aluminum, [(CH3)2AlSCH3]n, has been determined from three-dimensional X-ray data measured by counter methods. [(CH3)2AISCH3]n crystallizes in the orthorhombic space group Fdd2 with cell dimensions a = 25.679 (7) Å, b = 7.942 (2) Å, and c = 12.004 (3) Å. The calculated density of 1.13 g cm−3 for 16 (CH3)2AISCH3 units per unit cell compares well with the observed density of 1.14 ± 0.03 g cm-3. Three-dimensional least-squares refinement gave a conventional weighted R factor of 3.9% for 445 reflections. In the solid state, [(CH3)2AlSCH3]n is a one-dimensional infinite polymer with methylthiol groups bridging dimethylaluminum groups to form zigzag infinite chains. The bridging sulfur atoms are in a pyramidal configuration. The average Al-S bond length is 2.348 (2) Å, the average Al-C bond distance is 1.944 (7) Å, and the C-S bond length is 1.806 (7) Å. The Al-S-Al͇ angle is 103.0 (1)°, and the S-Al-Sʹ angle is 100.1 (1)°. © 1969, American Chemical Society. All rights reserved.