Terminal beryllium–hydrogen bonding in dimeric (2-dimethylamino-N-methylethylamido)hydridoberyllium, [Be2(C5H13N2)2H2]

Abstract

Abstract. Mr=222.38, triclinic, Pi, a= 7.463 (2) for 958 observed diffractometer data. Although the compound is trimeric in solution, it is dimeric in the solid state, with the two halves of the dimer being linked by a centrosymmetric fourmembered Be2N 2 ring. Be achieves a coordination number of four by formation of a dative Be,--N bond involving the second N atom of the ligand resulting in the formation of five-membered rings. This represents the first example of the structural characterization of a compound containing a terminal Be-H bond.

The structural characterization of the first beryllium amide possessing nitrogen-bridged Be(II) and Sn(IV) metal centers: Synthesis and X-ray study of [(Me3Sn)2NBe(Cl)·(THF)]2

“…This is due to the lack of structural data available for beryllium alkyl-or silylamides possessing unsubstituted chloride ligands. The tin-nitrogen interatomic distance [2.093(6) Å ] is also comparable to those found in previous structures containing similar bridging stannylamine ligands {[(Me 3 Sn) 2 NCu] 4 , Sn-N avg = 2.065 Å [8] and [(Me 3 Sn) 2 NLi AE MeOBu t ] 2 , Sn-N avg =2.032} [12].…”

“…Most of the structurally characterized beryllium amide complexes possess either alkyl or silyl amine ligands and tend to exist as dimers in the absence of bulky ligand substituents [1][2][3][4]. In a synthetic tour de force, Nö th and Schlosser [5] recently elucidated the synthesis for a large number of beryllium (II) amides containing alkyl and silyl amine ligands and unsubstituted chloride ligands, many of which were found to be dimeric in nature.…”

Synthesis,9Be NMR Spectroscopy, and Structural Characterization of Sterically Encumbered Beryllium Compounds

“…Since the beryllium-coordinated ether in the starting material has been eliminated, the berylliums are both three-coordinate in the product and the Be−C distances are very similar to those observed in 2 − 4 . The Be−N distances are in the range 1.690(6)−1.725(6) Å which is rather longer than the 1.653(7) Å observed for the Be(3-coord)−N (4-coord) distance in {Be(NMe 2 ) 2 } 3 23a and much longer than the 1.550(4) Å observed for the Be(3-coord)−N(3-coord) distance in the dimer {BeN(Me)SiMe 2 CH 2 SiMe 2 NMe} 2 23b23c…”

“…The Be−N distances are in the range 1.690(6)−1.725(6) Å which is rather longer than the 1.653(7) Å observed for the Be(3-coord)−N (4-coord) distance in {Be(NMe 2 ) 2 } 3 23a and much longer than the 1.550(4) Å observed for the Be(3-coord)−N(3-coord) distance in the dimer {BeN(Me)SiMe 2 CH 2 SiMe 2 NMe} 2 23b23c) by the reaction of LiNHSiPh 3 with 2 .…”

Molecular Main Group Metal Hydrides

“…The aminoberyllium hydride, [{Me 2 N­(CH 2 ) 2 NMe}­BeH] 2 ( 101 ), was prepared in 1968 by the direct deprotonation of N , N , N -trimethyl­ethylenediamine with beryllium dihydride and elimination of gaseous hydrogen (eq 18 ). Although initially assigned as a trimer on the basis of cryoscopic measurements, a dimeric structure was determined in the solid state by X-ray analysis in 1983, where each hydrogen atom bound to beryllium occupies a terminal position and the amido nitrogen atoms adopt bridging positions, leading to a four-membered Be 2 N 2 ring (Figure a). , Beryllium hydride complexes supported by tris­(pyrazolyl)­borate (Tp) and N -heterocyclic carbene (NHC) ligands have been isolated and fully characterized. The monomeric hydridoberyllium derivative (3- tBu Tp)­BeH ( 102 , 3- tBu Tp = 3- tert -butylpyrazolyl) was obtained via a salt metathesis reaction of the corresponding beryllium halides (3- tBu Tp)­BeX (X = Cl, Br) with Li­[AlH 4 ] (eq 19 ).…”