Dialkylamino-bis(trimethylsilyl)amino-chlorborane und ihre Reaktion mit Natrium-bis(trimethylsilyl)amid

Stereochemistry of some aminoboranes containing N-trimethylsilyl, -germyl, or -stannyl substituents

“…-90 °C but below that two distinct peaks could not be observed because of the overlap problem. Hence the AGC* value for 14 is a rather crude estimate using Tc = -95 Amino(bis(trimethylsilyl)amino)phenylborane (15) had a measurable barrier about the B-NH2 bond. For the NH2 resonance a coalescence temperature of 43 ± 2 °C and a no-exchange separation of 22.4 Hz were observed leading to a calculated AGC* value of 16.1 ± 0.2 kcal/mol.…”

“…Such a description Me, Si NMe2 // \\ ,N-B 1/ \ Me 3 Si a of the electron distribution in compounds of this type had been previously proposed by Geymayer and Rochow. 15 In this paper we wish to report the determination of the rotational barriers about the B-NMe2 bonds of a number of aminoboranes RR,NB(Ph)NMe2 containing N-trimethylsilyl, -germyl, or -stannyl substituents. Such a study would hopefully allow more definitive conclusions concerning the nature of the bonding in silicon-nitrogen-boron compounds such as 4.…”

Stability and stereochemistry of some amino(bis(trimethylsilyl)amino)boranes

“…The relatively high AG* values obtained for compounds 1-3 indicate that only the dialkylamino nitrogen is strongly x bonded to boron16 in these compounds since bis (amino) boranes typically have much lower rotational barriers (ca. [10][11] keal/mol).17™19 This conclusion is supported by the results of a recent study19 which demonstrated that in related compounds such as (Me3Si)2NB(Ph)NMe2, "the bulky bis(trimethyl- silyl)amino group is rotated out of the plane of the B-NMe2 moiety and thus is not an effective x-donor to boron." The high AG* values also observed for compounds 4-6, therefore, lead one to conclude that, even in these tris(amino)boranes the bis(trimethylsilyl)amino substituent is twisted (ca.…”

Bis(diorganylamino)dihalodiboroxanes as Building Blocks for Boron Heterocycles

“…Starting materials were prepared according to the following references: ( i -Pr) 2 NBCl 2 , ( n -Pr) 2 NBCl 2 , ( i -Bu) 2 NBCl 2 , ( s -Bu) 2 NBCl 2 , c-C 6 H 11 N(CH 3 )BCl 2 , , ( i -Pr) 2 NBBr 2 , Me 2 NBCl 2 , Et 2 NBCl 2 , and (c-C 6 H 11 ) 2 NBCl 2 …”