Insertion Reaction of Me₃SiN₃with Bis(germylene)

Abstract

Herein, we describe the redox reaction of bis(germylene) PhC(N t Bu)2Ge–Ge(N t Bu)2CPh with different equivalents of Me3SiN3 affording two distinct products. The reaction of Me3SiN3 with bis-germylene in a 1:1 molar ratio results in compound 1 at −78 °C; however, treatment of bis-germylene with a 2.1 equiv of Me3SiN3 at room temperature results in compound 2. The formation of 1 and 2 can be rationalized by two successive 3 + 1 cycloadditions of Me3SiN3 with the germanium center of bis(germylene) and N2 elimination. All of the compounds are well-characterized by various spectroscopic techniques and single-crystal X-ray structural analyses. Density functional theory (DFT) calculations suggest that compound 2 has a dicoordinated nitrogen atom, which is stabilized by hyperconjugative interactions, resulting in pseudo-germylimine moiety. However, the dicoordinated nitrogen atom shows high basicity as indicated by proton affinity values. These are rare examples of isolated products that show insertion as well as simultaneous redox properties of bis(germylene).

Reactions of main group compounds with azides forming organic nitrogen-containing species

“…In 2022, Parameswaran, Stalke and Roesky et al reported the reaction of bis(germylene) Ge17 with azides (Scheme 92). 156 The addition of TMSN 3 into the toluene solution of Ge17 led to the formation of Ge17-P1 in 52% yield via the formal insertion of nitrene into the Ge–Ge bond. Ge17-P1 has the two central Ge–N bonds of 1.8821(12) and 1.9062(12) Å, indicative of typical Ge–N single bonds.…”

Synthesis of Si(IV)- and Ge(II)-Substituted Amines, Hydrazone, and Hydrazine from Hypersilyl Germylene

“…In 2020, Li et al presented the insertion of Me 3 SiN 3 between two Ge atoms in an amidinate system . Similar insertion of “N­(SiMe 3 )” moiety between two germanium atoms was reported by the groups of Roesky and Stalke by reacting the Ge­(I) compound, PhC­(N t Bu) 2 Ge–Ge­(N t Bu) 2 CPh with Me 3 SiN 3 …”

“…20 Similar insertion of "N(SiMe 3 )" moiety between two germanium atoms was reported by the groups of Roesky and Stalke by reacting the Ge(I) compound, PhC(NtBu) 2 Ge−Ge(NtBu) 2 CPh 21 with Me 3 SiN 3 . 22 The reaction of PhC(NtBu) 2 GeSi(SiMe 3 ) 3 (1) with adamantyl azide did not form the expected germanimine compound, but rather an amine (2) with three different substituents (Scheme 2) possessing three different group 14 elements. Although the mechanism for the formation of 2 has not been definitively established, we assume that initially there is a germanimine formation, PhC(NtBu) 2 Ge(�NAd)Si-(SiMe 3 ) 3 .…”

Mechanistic Insights Into the [3+1] Cycloadditions of Me3SiN3 on Bis‐Silylene and the Formation of Pseudo‐Silaazatriene

“…Our earlier studies indicate that even though, the lone pairs on the dicoordinated nitrogen atoms are stabilized by hyperconjugative interactions, they are prone to electrophilic attack. [23,37] The σ-type lone pair of the N di center in I2 has the right symmetry to interact with the SiÀ N σ* orbital of the tricoordinated silicon centre (Figure S4). The coordination of dicoordinated nitrogen atom is expected to result in a highly The intermediate I3 has a bridged NÀ SiMe 3 group placed between the two silylene fragments.…”

“…We have recently reported a germylamine by the reaction of bis-germylene (LGeÀ GeL; L = PhC(N t Bu) 2 ) and Me 3 SiN 3 which is analogous to the intermediate I3. [37] The higher reactivity of the silicon lone pair in I3 as compared to the germanium lone pair in germylamine might be the reason for the elusive nature of the former. The enhanced reactivity of I3 is supported by the higher negative MESP value (À 35. formation of the resulting intermediate I4 is slightly less exothermic (À 24.3 kcal/mol) and exergonic (À 7.8 kcal/mol) than the same for the formation of I1 (Scheme 3, Figure 4).…”