Darstellung und Molekülstruktur von Tris(dimethyldithiocarbamato)aluminium, eine Verbindung mit hexakoordiniertem Aluminium

Abstract

AI(NR,), und ClAI(NR,), (R = CH,) addieren CS, unter Bildung der Dimethyldithiocarbamate 1 und 2, von denen 1 in Benzol monomer, 2 hingegen dimer ldslich ist. 27Al-NMR-Daten weisen hexakoordinierte Al-Atome aus, die durch die Rontgenstrukturanalyse von 1 bestatigt werden: das Al-Atom ist verzerrt trigonal antiprismatisch von sechs Schwefelatomen umgeben. Die C2NCS2-Gruppen sind planar. Fur 2 folgt eine Struktur mit zwei briickenstandigen C1-Atomen, jeweils vier S-Atome erganzen zur Hexakoordination der zwei Al-Atome im Molekul. Preparation and Molecular Structure of Tris(dimethyldithiocarbamato)aluminium, a Compound with Hexacoordinated Aluminium *)Al(NR,), and C1A1(NR2), (R = CH,) add CS, with formation of the dimethyldithiocarbamates 1 and 2. 1 dissolves in benzene as a monomer in contrast to dimeric 2. 27Al NMR data indicate the presence of hexacoordinated A1 atoms which are ascertained by an X-ray structure determination of 1: its A1 atom is surrounded in a distorted trigonal antiprismatic fashion by six sulfur atoms. The C,NCS, groups are planar. 2 possesses a structure containing two bridging C1-atoms with four sulfur atoms each to complete hexacoordination for the two A1 atoms in the molecule.

Synthesis and Reactivity of New Bis(tetramethylpiperidino)(phosphanyl)alumanes

“…A single-crystal X-ray structure determination for Al(S 2 CNMe 2 ) 3 confirmed the formation of an unusual six coordinate aluminum center with bidentate dithiocarbamate chelation. [18] In close parallel to the present study, we have also previously observed CO 2 insertion in Al-N bonds in tmpAl fragments. [5,8] With the (amino)(phosphanyl)alumane, 2, the question of interest was: will this reagent, with both Al-N and Al-P bonds, undergo selective insertion or insertion in all Al-N and Al-P bonds?…”

“…The spectra for 2-4 can be compared with data for 1 and tmp 2 AlPPh 2 , [5] and the spectra for 5-8 can be examined against data for [MeAl-(O 2 Ctmp) 2 ] 2 , [5] [(tBuAl) 2 - [8] and Al(S 2 CNMe 2 ) 3 . [18] In each of the new compounds 2-8, the 1 H and 13 C{ 1 H} spectra are consistent with a single tmp group environment with free rotation about the Al-N bonds and rapid ring inversion. These spectra also show a single Me 3 Si or Me 3 Sn environment.…”

“…In the current context, we have previously reported the reactions of Al(NMe 2 ) 3 and Al(Cl)(NMe 2 ) 2 with CO 2 [19] and CS 2 . [18] Each Al-N bond undergoes insertion with the formation of the corresponding carbamate or dithiocarbamate compounds, Al(X 2 CNMe 2 ) 3 and Al(Cl)(X 2 CNMe 2 ) 2 (X = O or S). A single-crystal X-ray structure determination for Al(S 2 CNMe 2 ) 3 confirmed the formation of an unusual six coordinate aluminum center with bidentate dithiocarbamate chelation.…”

“…Historically, another reactivity pathway of interest in our group is that involving insertion reactions into P-N, [16] B-N [17] and Al-N [18] bonds. In the current context, we have previously reported the reactions of Al(NMe 2 ) 3 and Al(Cl)(NMe 2 ) 2 with CO 2 [19] and CS 2 .…”

Alkylthiolatoalanes and Alkylthiolatohydridoaluminates

“…In addition, the average AlϪS bond length Al (6) ϪS (2) has been found to be 2.399 Å . [22] (Coordination numbers are set here in superscript). Therefore, we observe an increase in the AlϪS bond lengths as the coordination number of sulfur increases.…”