Rare‐Earth‐Metal‐Promoted Hydroalumination

Abstract

The capability of bis(trimethylsilyl)amidoalane to act as a hydride transfer reagent in organolanthanide chemistry was investigated by probing its reactivity toward alkylyttrium complexes. Reaction with Cp*2YMe(thf) led to the isolation of the bimetallic complex Cp*2Y(μ‐H)2Al(Me)[N(SiMe3)2] (Cp* = 1,2,3,4,5‐pentamethylcyclopentadiene), whereas reaction with [Cp*YMe2]3 gave MeAl[N(SiMe3)2]2 as the only isolable hydride transfer product. The dimeric complex [Cp*Y{N(SiMe3)2}(μ‐H)]2 represents one possible product of the aforementioned reaction that could be structurally characterized. The use of [YMe3]n as the alkylyttrium source led to the isolation of Y[N(SiMe3)2]3, which displays competition between amide and hydride transfer. Finally, the performance of Cp*2Y(μ‐H)2Al(Me)[N(SiMe3)2] and [YMe3]n in the hydroalumination of 1‐octene was tested, and these compounds represent the first rare‐earth metal catalysts for this transformation.

The role of the bis-trimethylsilylamido ligand, [N{SiMe3}2]−, in main group chemistry. Part 2: Structural chemistry of the metallic p-block elements

“…Bridging hydrides were observed in the bimetallic compound [Al( -H)(N{SiMe 3 } 2 ) 2 ] 2 ([12] 2 ) whereas the non-symmetric dimer, Al(N{SiMe 3 } 2 )(NMe 2 )( -NMe 2 ) 2 AlH(N{SiMe 3 } 2 ) (13) contained bridging NMe 2 groups [20]. Recently it was shown that the reaction of 7 with SiMe 3 Cl afforded [12] 2 in 98% isolated yield [21]. The reaction of 12 with YCp* 2 Me(THF) afforded the bimetallic compound YCp* 2 ( -H) 2 AlMe(N{SiMe 3 } 2 ) (14) and Al(N{SiMe 3 } 2 ) 3 (1) [21].…”

“…Recently it was shown that the reaction of 7 with SiMe 3 Cl afforded [12] 2 in 98% isolated yield [21]. The reaction of 12 with YCp* 2 Me(THF) afforded the bimetallic compound YCp* 2 ( -H) 2 AlMe(N{SiMe 3 } 2 ) (14) and Al(N{SiMe 3 } 2 ) 3 (1) [21].…”

“…Related 69-atom clusters, [Al 69 (N{SiMe 3 } 2 ) 18 ] 3− ( [18]) and the oxidized species, [Al 69 (N{SiMe 3 } 2 ) 18 ] 2− ( [19]) were synthesized using "AlCl" as the metal source [25]. The smaller clusters, [Al 7 (N{SiMe 3 } 2 ) 6 ] − ( [20]) [26], and [Al 12 (N{SiMe 3 } 2 ) 8 ] − ( [21], Fig. 4) [27], have also been reported.…”

Lanthanides and actinides: Annual survey of their organometallic chemistry covering the year 2013

“…Therein, the olefin reacts in a first step with bimetallic complex A to form the mixed alkyl complex C possibly via a four-membered metallacycle intermediate B. Next, alkyl hydride exchange occurs with E to regenerate starting material A and amidoaluminum alkyl F via four-membered metallacycle D [111]. The efficiency of several chiral alkyl or amido yttrium complexes prepared from N-silyl-or N-cyclopentyl-substituted binaphthylamido ligands (cf.…”

Rare‐Earth Catalyzed C−H Bond Alumination of Terminal Alkynes

“…Lanthanide aluminates, upon activation,a re typicallyc atalyst precursors for alkene and diene polymerization and are also used to generate highly reactive species such as masked alkylidenes and cationic alkyls. [29][30][31][32][33][34][35][36][37][38][39][40] In the few reports of aluminum addition chemistry,p iano-stool scandium compounds catalyze the carboalumination of ether-containing alkynes, [41] and bentsandwich yttrium compounds catalyze hydroalumination, [42] together suggesting that the appropriate ancillary ligands also are required to promote alumination pathways. In the initial phase of this work, we communicatedt hat an eodymium aluminate supported by ac yclopentadienylborate ligand, {Me 2 Al(Ox Me2 ) 2 BPh(C 5 H 4 )}Nd(AlMe 4 ) 2 (1 Nd ;O x Me2 = 4,4-dimethyl-2-oxazoline), is ac atalyst for aluminationo ft erminal alkynes.…”