1428342-12-4

Upstream product

• 1428342-10-2 C₄₀H₆₂N₂Si 
• 1449240-91-8 C₄₀H₆₂GeN₂ 
• 10024-97-2 dinitrogen monoxide 

Relevant academic research and scientific papers

Dioxygen activation with stable N-heterocyclic carbenes

Dioxygen activation with both cyclic (amino)(alkyl)carbenes and di(amino)carbenes at ambient temperature is described. Theoretical studies suggest that electron rearrangement from the doubly filled σ orbital of carbene carbon to its vacant p orbital through the π? antibonding orbital of 3O2 can be considered for Ccarbene-O bond formation.

Easy access to silicon(0) and silicon(II) compounds

Two different synthetic methodologies of silicon dihalide bridged biradicals of the general formula (Ln?)2SiX 2 (n = 1, 2) have been developed. First, the metathesis reaction between NHC:SiX2 and Ln: (Ln: = cyclic akyl(amino) carbene in a 1:3 molar ratio leads to the products 2 (n = 1, X = Cl), 4 (n = 2, X = Cl), 6 (n = 1, X = Br), and 7 (n = 2, X = Br). These reactions also produce coupled NHCs (3, 5) under C-C bond formation. The formation of the coupled NHCs (Lm = cyclic alkyl(amino) carbene substituted N-heterocyclic carbene; m = 3, n = 1 (3) and m = 4, n =2 (5)) is faster during the metathesis reaction between NHC:SiBr2 and L n: when compared with that of NHC:SiCl2. Second, the reaction of L1:SiCl4 (8) (L1: =:C(CH 2)(CMe2)2N-2,6-iPr2C 6H3) with a non-nucleophilic base LiN(iPr)2 in a 1:1 molar ratio shows an unprecedented methodology for the synthesis of the biradical (L1?)2SiCl2 (2). The blue blocks of silicon dichloride bridged biradicals (2, 4) are stable for more than six months under an inert atmosphere and in air for one week. Compounds 2 and 4 melt in the temperature range of 185 to 195 C. The dibromide (6, 7) analogue is more prone to decomposition in the solution but comparatively more stable in the solid state than in the solution. Decomposition of the products has been observed in the UV-vis spectra. Moreover, compounds 2 and 4 were further converted to stable singlet biradicaloid dicarbene-coordinated (L n:)2Si(0) (n = 1 (9), 2 (10)) under KC8 reduction. Compounds 2 and 4 were also reduced to dehalogenated products 9 and 10, respectively when treated with RLi (R = Ph, Me, tBu). Cyclic voltametry measurements show that 10 can irreversibly undergo both one electron oxidation and reduction.

Acyclic germylones: Congeners of allenes with a central germanium atom

The cyclic alkyl(amino) carbene (cAAC:)-stabilized acyclic germylones (Me2-cAAC:)2Ge (1) and (Cy2-cAAC:) 2Ge (2) were prepared utilizing a one-pot synthesis of GeCl 2(dioxane), cAAC:, and KC8 in a 1:2:2.1 molar ratio. Dark green crystals of compounds 1 and 2 were produced in 75 and 70% yields, respectively. The reported methods for the preparation of the corresponding silicon compounds turned out to be not applicable in the case of germanium. The single-crystal X-ray structures of 1 and 2 feature the C-Ge-C bent backbone, which possesses a three-center two-electron π-bond system. Compounds 1 and 2 are the first acyclic germylones containing each one germanium atom and two cAAC: molecules. EPR measurements on compounds 1 and 2 confirmed the singlet spin ground state. DFT calculations on 1/2 revealed that the singlet ground state is more stable by ～16 to 18 kcal mol-1 than that of the triplet state. First and second proton affinity values were theoretically calculated to be of 265.8 (1)/267.1 (2) and 180.4 (1)/183.8 (2) kcal mol -1, respectively. Further calculations, which were performed at different levels suggest a singlet diradicaloid character of 1 and 2. The TD-DFT calculations exhibit an absorption band at ～655 nm in n-hexane solution that originates from the diradicaloid character of germylones 1 and 2.