693228-12-5Relevant academic research and scientific papers
Reactions of the heavier group 14 element alkyne analogues Ar′EEAr′ (Ar′ = C6H3-2,6(C 6H3-2,6-Pri2)2; E = Ge, Sn) with unsaturated molecules: Probing the character of the EE multiple bonds
Cui, Chunming,Olmstead, Marilyn M.,Fettinger, James C.,Spikes, Geoffrey H.,Power, Philip P.
, p. 17530 - 17541 (2005)
Reactions of the alkyne analogues Ar′EEAr′ (Ar′ = C 6H3-2,6(C6H3-2,6-Pri 2)2; E = Ge (1); Sn (2)) with unsaturated molecules are described. Reaction of 1 and 2 with azobenzene afforded the new hydrazine derivatives Ar′E{(Ph)NN(Ph)}EAr′ (E = Ge (3); Sn (4)). Treatment of 1 with Me3SiN3 gave the cyclic singlet diradicaloid Ar′Ge{μ2-(NSiMe3)}2GeAr′ (5), whereas 2 afforded the monoimide bridged Ar′Sn{μ2- N(SiMe3)}-SnAr′ (6). Reaction of 1 with t-BuNC or PhCN yielded the adduct Ar′GeGe(CNBui)Ar′ (7) or the ring compound Ar′Ge-N(Ph)CC(Ph)N-GeAr′ (8). In contrast, the tin compound 2 did not react with either t-BuNC or PhCN. Treatment of 1 with N 2CH(SiMe3) generated Ar′Ge{μ2- CH(SiMe3)}{μ2:η2-N 2CH(SiMe3)}{μ2-N2-CH(SiMe 3)}GeAr′ (9) which contains ligands in three different bridging modes and no Ge-Ge bonding. Reaction of 1 with an excess of N2O gave a germanium peroxo species Ar′(HO)Ge(μ2-O) (μ2:η2-O2)Ge-(OH)Ar′ (10) which features a Ge-O-Ge-O-O ring. Oxidation of 1 by tetracyanoethylene (TCNE) led to cleavage of the Ge-Ge bond and formation of a large multiring system of formula Ar′Ge3+{(TCNE)2-}3- {(GeAr′) +}3. The digermyne 1 also reacted with 1 equiv of Ph≡CPh to give the 1,2-digermacyclobutadiene 12, which has a Ge-C-C-Ge ring, and with Me3SiC≡CH or PhC≡C-C≡CPh to activate a flanking C6H3-2,6-Pri2 ring and give the tricyclic products 13 and 14. The distannyne 2 did not react with these acetylenes. Overall, the experiments showed that 1 is highly reactive toward unsaturated molecules, whereas the corresponding tin congener 2 is much less reactive. A possible explanation of the reactivity differences in terms of the extent of the singlet diradical character of the Ge-Ge and Sn-Sn bonds is discussed.
Reactivity of Ar′GeGeAr′ (Ar′ = C6H 3-2,6-Dipp2, Dipp = C6H 3-2,6-iPr2) toward Alkynes: Isolation of a Stable Digermacyclobutadiene
Cui, Chunming,Olmstead, Marilyn M.,Power, Philip P.
, p. 5062 - 5063 (2007/10/03)
The first reactions of the digermyne Ar′GeGeAr(Ar′ = C6H3-2,6-Dipp2, Dipp = C6H3-2,6-iPr2) with alkynes are reported. 1 reacts with 1 equiv of H5C6CCC6H5 to afford the 1,2-digermacyclobutadiene 2 in high yield, while it reacts with 2 equiv of the less hindered alkyne Me3SiCCH to yield an unexpected bicyclic compound 3. Molecular structures of 2 and 3 were determined by X-ray crystallography. A possible mechanism for the formation of 3 is discussed. The high reactivity of 1, even at room temperature, emphasizes the fundamental differences between the GeGe and CC multiple bonds. Copyright
