438201-89-9Relevant academic research and scientific papers
Versatile reactivity of phosphagermaallene tip(t -Bu)Ge=C=PMes* with α-ethylenic esters
Ghereg, Dumitru,Ouhsaine, Fatima,Escudie, Jean,Labat, Stephane,Andre, Erwan,Miqueu, Karinne,Sotiropoulos, Jean-Marc,Gornitzka, Heinz,Saffon, Nathalie
, p. 1085 - 1093 (2013)
The phosphagermaallene Tip(t-Bu)Ge=C=PMes* (1) (Tip = 2,4,6-triisopropylphenyl, Mes* = 2,4,6-tri-tert-butylphenyl) reacts with methyl crotonate, methyl cinnamate, and methyl fumarate according to a [2+2] cycloaddition between the Ge=C and C=O double bonds to afford oxagermacyclobutanes 2-4. With methyl maleate, a [2+4] cycloaddition is observed between the Ge=C double bond and the O=C-C=C moiety, leading to oxagermacyclohexene 5. With methyl acrylate, phosphagermaallene 1 behaves as a 1,3-dipole, giving a transient five-membered-ring germa(phosphino)carbene, which rearranges by insertion of the carbenic carbon atom into a CH bond of a tert-butyl group of the Mes* group to afford the tricyclic derivative 8. These results have been supported by a theoretical approach in order to describe the reaction pathways and explain the different experimental results.
Comparison of reactivity of phosphagermaallene Tip(t-Bu)GeCPMes* towards sulfur ylides
Kocsor, Tibor-Gabor,Deak, Noemi,Ghereg, Dumitru,Nemes, Gabriela,Escudié, Jean,Gornitzka, Heinz,Ladeira, Sonia,Castel, Annie
, p. 120 - 124 (2014/03/21)
Phosphagermaallene 1, Tip(t-Bu)GeCPMes* (Tip = 2,4,6- triisopropylphenyl, Mes* = 2,4,6-tri-tert-butylphenyl), reacts with diphenylsulfoniumylide (Ph2SCH2) leading to adduct 2, through a nucleophilic attack of the negatively charged carbon atom of the ylide on the positively charged germanium atom followed by a migration of one of the phenyl groups. By contrast, dimethyloxosulfoniummethylide (Me 2S(O)CH2) appears much less reactive towards 1: it preferentially undergoes an in-situ oxidation of THF leading to a γ-butyrolactone intermediate which gives a [2+2] cycloaddition by the CO group with the GeC double bond to form 3. The new compounds 2 and 3 were completely characterized by multinuclear NMR spectroscopy and by single crystal X-ray structural analysis.
The reactivity of phosphagermaallene Mes*P=C=Ge(t -Bu)tip toward aldehydes and ketones: An experimental and theoretical study
Ouhsaine,Andre,Sotiropoulos,Escudie,Ranaivonjatovo,Gornitzka,Saffon,Miqueu,Lazraq
, p. 2566 - 2578 (2010/08/05)
Phosphagermaallene Mes*P=C=Ge(t-Bu)Tip 1 (Tip = 2,4,6- triisopropylphenyl, Mes* = 2,4,6-tri-tert-butylphenyl) has been obtained by an improved synthesis in relation to the previously reported preparation starting from t-BuGeCl3. Very short Ge=C (1.761(2) A) and P=C (1.625(2) A) double bond lengths, trigonal planar geometry around the Ge atom, and GeCP bond angle of 166.57° are indicative of an heteroallenic structure for 1. Its reactions with crotonaldehyde and cinnamaldehyde lead to 1-oxa-2-germacyclobutanes by a [2 + 2] cycloaddition between the Ge=C and C=O double bonds; with methyl vinyl ketone, both a [2 + 4] cycloaddition between the Ge=C and the O=C-C=C moieties and an ene-reaction are observed leading to a 1-oxa-2-germacyclohex-5-ene and a germyl(butadienyl)ether, respectively. With acetophenone, an ene-reaction occurs to afford exclusively a germyl(vinyl)ether. DFT calculations have been performed to explain the regiochemistry observed.
The reactivity of phosphagermaallene tip(t-Bu)Ge=C=PMes* with doubly and triply bonded nitrogen compounds
Ghereg, Dumitru,Gornitzka, Heinz,Escudie, Jean,Ladeira, Sonia
, p. 10497 - 10505 (2011/01/12)
Phosphagermaallene Tip(t-Bu)Ge=C=PMes* (1; Mes* = 2,4,6-tri-tert-butylphenyl, Tip = 2,4,6-triisopropylphenyl) gives, with N-benzylidenemethylamine and pivalonitrile, [2+2] cycloadditions between the Ge=C double bond and the C=N and C≡N unsaturations, leading to the formation of the corresponding four-membered heterocycles 2 and 9. With N-tert-butyl-α-phenylnitrone and benzonitrile oxide, [2+3] cycloadditions occur to form the five-membered ring derivatives 6 and 7. By treatment of 1 with derivatives which possess weak acidic hydrogens in α of the C=N or C≡N multiple bond, two types of reactions were observed: an ene reaction with methyl(benzylideneamino)acetate and a 1,2 addition with acetonitrile to afford azadienyl(germyl)ether (4) and 3-germa-1-phosphapropene (8), respectively. In the case of benzonitrile, phosphagermaallene 1 behaves as a 1,3-dipole, to give, via a cyclic phosphagermacarbene intermediate, the tricyclic derivative 10.
From a phosphagermaallene -P=C=Ge< and heavier chalcogens (S, Se, Te): Access to 3-phosphanylidene-l,2-chalcogenagermiranes
Ouhsaine, Fatima,Ranaivonjatovo, Henri,Escudie, Jean,Saffon, Nathalie,Lazraq, Mohamed
, p. 1973 - 1975 (2009/08/15)
Chalcogenagermiranes that feature an exocyclic P=C double bond were obtained from the phosphagermaallene Mes*P= C=Ge(t-Bu)Tip (Mes* = 2,4,6-tritert-butylphenyl, Tip = 2,4,6-triisopropylphenyl) and heavier chalcogens. The structural data of selena- and telluragermiranes show they are intermediate between a normal three-membered ring and a π-complex.
The first stable 3,1-germaphosphaallene Tip(t-Bu)Ge=C=PAr
Harouch, Yamna El,Gornitzka, Heinz,Ranaivonjatovo, Henri,Escudié, Jean
, p. 202 - 208 (2007/10/03)
The first stable heteroallenic derivative with two heavy doubly-bonded Group 14 and 15 elements, the germaphosphaallene Tip(t-Bu)Ge=C=PAr 1 (Tip = 2,4,6-triisopropylphenyl, Ar = 2,4,6-tri-tert-butylphenyl), has been prepared in a nearly quantitative yield by dechlorofluorination of Tip(t-Bu)Ge(F)-C(C1)=PAr (obtained from ArP=CC12 and successive reaction with n-butyllithium and Tip(t-Bu)GeF2) with tert-butyllithium. 1 gives [2 + 2] cycloadducts by the Ge=C double bond with benzaldehyde, benzophenone and fluorenone to afford the corresponding germaoxetanes 11 - 13. 13 has been structurally characterized showing a long Ge-O bond (1.821(2) ?) and a slightly folded four-membered ring GeOCC (18.8° along C(1)Ge axis).
