Chemistry:Germyl

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Germyl
Names
IUPAC name
Germanide
Other names
Trihydridogermanate(1-)
Trihydridogermanate(IV)
Trihydrogen germanide
Trihydrogermanide
Trihydridogermyl
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
305156
Properties
GeH
3
Molar mass 75.654 g·mol−1
Related compounds
Other cations
Silanide (-SiH3);
Stannyl (-SnH3)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Germyl, trihydridogermanate(1-), trihydrogermanide, trihydridogermyl or according to IUPAC Red Book: germanide[1] is an anion containing germanium bounded with three hydrogens, with formula GeH
3
. Germyl is the IUPAC term for the –GeH
3
group. For less electropositive elements the bond can be considered covalent rather than ionic as "germanide" indicates. Germanide is the base for germane when it loses a proton.

GeH
4
→ GeH
3
+ H+

The first germyl compound to be discovered was sodium germyl. Germane was reacted with sodium dissolved in liquid ammonia to produce sodium germyl.[2][3] Other alkali metal germyl compounds are known. There are also numerous transition metal complexes that contain germyl as a ligand.

Formation

Alkali metal germyl compounds have been made by reacting germane with the alkali metal dissolved in liquid ammonia, or other non-reactive solvent.

Transition metal complexes cam be made by using lithium aluminium hydride to reduce a trichlorogermyl complex (−GeCl
3
), which in turn can be made from the transition metal complex chloride and GeCl
2
.[4]

Salt elimination can be used in a reaction with monochlorogermane and a sodium salt of a transition metal anion:

GeClH
3
+ NaMn(CO)
5
→ NaCl + Mn(GeH
3
)(CO)
5
.[4]

In the gas phase, the germyl anion GeH
3
can be made from germane by capturing an electron with more than 8 eV of energy:

GeH
4
+ e
→ GeH
3
+ H
[5]

The germyl radical can be produced and immobilised in molecular form by exposing germane to vacuum ultraviolet light in a solid argon matrix. On heating, digermane is formed:

2 GeH
3

→ GeH
3
GeH
3
[6]

Properties

Germyl compounds react with water, so water cannot be used as a solvent. Liquids that have been used as solvents include liquid ammonia, ethyl amine, diglyme, or hexamethylphosphoramide. The choice of solvent depends on the temperature desired, whether alkali metals are going to be dissolved, whether the solvent needs to be distilled, and also if it reacts with the solute.[7]

The bond between the metal ion and the germyl ion may be purely ionic, but may also be bonded via two bridging hydrogen atoms.[8]

The energy to rip a hydrogen atom off germane to make the neutral radical is 82.0±2 kcal/mol. GeH4 → GeH3 + H.[5] Electron affinity for the radical is 1.6 eV: GeH3 + e → GeH3.[5]

Gas phase acidity of germane is ΔG°acid is 350.8±1.3 kcal/mol; ΔH°acid is 358.9 kcal/mol for GeH
4
→ GeH
3
+ H+
.[5]

Both the anion GeH
3
and radical GeH3 have C3v symmetry, and are shaped as a triangular pyramid with germanium at the top, and three hydrogen atoms at the bottom.[5] In the radical, the H-Ge-H angle is 110°. In the anion the H-Ge-H angle is about 93°.[5]

Reactions

Germyl compounds gradually decompose at room temperature by releasing hydrogen and forming a metal germide.[3]

Germyl compounds react with alkyl halides to substitute the germyl −GeH
3
group for the halogen. With aromatic halide compounds, dihalomethanes, or neopentyl haldes they replace the halogen with hydrogen.[2] Organogermanium compounds that can be produced include methyl germane, dimethyl germane, digermyl methane, digermyl ethane, digermyl propane.[2]

The germyl ion reacts with water to yield germane:

GeH
3
+ H
2
O → GeH
4
+ OH
[3]

Sodium germyl reacts with oxygen to form an orthogermanate:

NaGeH
3
+ O
2
→ NaOGe(OH)
3

This loses water at room temperature.[3]

K[η5-C5H5)Mn(CO)2GeH3] reacts with acid to yield [η5-C5H5)Mn(CO)2]2Ge which has a Mn=Ge=Mn linkage in it.[9]

List

formula name mw system space group unit cell volume density comments ref
LiGeH
3
[10]
LiGeH3•2NH3 [11]
NaGeH
3
Sodium Trihydrogermanide white [3]
NaGeH3•2NH3 [3]
NaGeH3•4.5NH3 [3]
NaGeH3•6NH3 [3]
P(GeH3)3 [12]
KGeH3 cubic a=7.235 2.003 NaCl structure [13][10]
K([18]crown-6)(thf)GeH3 451.13 monoclinic Pc a=13.8587 b=9.9670 c=16.9439 β=107.206 Z=4 2235.7 1.34 colourless [8]
K([15]crown-5)2GeH3 555.23 tetrahedral I4 a=12.685 c=16.985 Z=4 2733.0 1.349 colourless [8]
K([12]crown-4)2GeH3 467.13 monoclinic C2/c a=40.7694 b=6.623 c=29.6746 β=97.450 Z=16 9144.9 1.357 colourless [8]
K[V(CO)35-C5H5)GeH3] [14]
[PPh4][V(CO)35-C5H5)GeH3] orthorhombic Pcab a=17.47 b=15.68 c=21.49 Z=8 5886 1.39 yellow [14][15]
K[Cr(CO)5GeH3] [16]
[PPh4][Cr(CO)5GeH3] monoclinic C2/c a=22.301 b=6.989 c=18.002 β=? Z=4 2788.5 1.45 yellow [16][15]
Mn(GeH3)(CO)5 [9]
Mn(GeH3)(CO)2(PPh(OEt)2)3 pale yellow [4]
Mn(GeH3)(CO)3(PPh(OEt)2)2 610.96 triclinic P1 a=10.118 b=11.060 c=13.009 α=97.859 β=98.612 γ=92.856 Z=2 1422.3 1.427 pale yellow [4]
Mn(GeH3)(CO)2(P(OEt)3)3 pale yellow [4]
Mn(GeH3)(CO)3(P(OEt)3)2 pale yellow [4]
K[η5-C5H5)Mn(CO)2GeH3] [9]
[(CH3)4N][η-CH3C5H4Mn(CO)2GeH3] triclinic P1 a=6.948 b=9.658 c=11.784 α=89.57 β=77.37 γ=88.05 Z=2 772 1.45 [17]
[(CH3)4N][η-CH3C5H4Mn(CO)2GeH3] triclinic P1 a=6.958 b=9.658 c=11.784 α=89.57 β=77.37 γ=88.05 Z=2 772 1.46 [18]
(GeH3)2Fe(CO)4 digermyltetracarbonyliron mp 71°C colourless [19]
GeH3(H)Fe(CO)4 monogermylhydridotetracarbonyliron mp −30°C colourless [19]
GeH3Fe(C5H5)(CO)2 Germyl(cyclopentadienyl)dicarbonyliron mp 81°C yellow [19]
Fe(CO)4(GeH2GeH3)(GeH3) [20]
Fe(CO)4(GeH3)(GeMe3) [21]
{Fe(CO)4(GeH2)}2 -Fe-Ge-Fe-Ge- ring [22]
K[Co2(CO)7GeH3] [16]
[PPh4]Co2(CO)7GeH3] [16]
K[Co-(CO)(η5C6H5)GeH3] [14]
[PPh4][Co-(CO)(η5C6H5)GeH3] [14]
K[Co-(CO)(η5C6(CH3)5)GeH3] [14]
[PPh4][Co-(CO)(η5C6(CH3)5)GeH3] [14]
K[(η5-C5H5)-Mn(CO)2GeH3] [16]
K[Ni(CO)3GeH3] [14]
[PPh4][Ni(CO)3GeH3] monoclinic C2 a=16.855 b=7.098 c=15.189 β=134.71 Z=2 1291.5 1.43 orange yellow [14][15]
K[Ni(CO)2(PPh3)GeH3] [14]
[PPh4][Ni(CO)2(PPh3)GeH3] monoclinic P21/n a=10.37 b=22.37 c=16.95 β=96.23 Z=4 2910.6 1.74 orange yellow [14][15]
As(GeH3)3 [12]
Rb([18]crown-6)(thf)GeH3 497.50 monoclinic Cc a=13.8336 b=9.9878 c=16.9893 β=107.417 Z=4 2239.7 1.475 colourless [8]
RbGeH3 a=7.518 2.518 [10]
K[Nb(CO)35-C5H5)GeH3] [14]
[PPh4][Nb(CO)35-C5H5)GeH3] [14]
K[Mo(CO)5GeH3] [14]
[PPh4][Mo(CO)5GeH3] monoclinic C2/c a=22.25 b=7.021 c=18.545 β=96.14 Z=4 2881 1.5 yellow [14][15]
Ru(GeH3)(η5-C5H5)(PPh3)P(OMe)3 628.12 monoclinic P21/c a=17.932 b=10.067 c=16.375, β=114.508° Z=4 2689.6 1.551 yellow [23]
Ru(GeH3)(η5-C5H5)(PPh3)P(OEt)3 yellow [23]
Ru(GeH3)(η5-C5H5)(PPh3)PPh(OEt)2 yellow [23]
Ru(GeH3)(η5-C9H7)(PPh3)P(OMe)3 yellow [23]
Ru(GeH3)(η5-C9H7)(PPh3)P(OEt)3 yellow [23]
Ru(GeH3)(η5-C9H7)(PPh3)PPh(OEt)2 yellow [23]
Ru(GeH3)(Tp)(PPh3))P(OEt)3 yellow [23]
Ru(GeH3)(Tp)(PPh3)PPh(OEt)2 yellow [23]
cis-[Ru(dppe)2(GeH3)H]•C6H6 1014.4 triclinic P1 a 12.3464 b 13.2412 c 16.2053, α 90.055° β 98.868° γ 116.164° Z=2 2342.3 1.438 [24]
trans-[Ru(dppe)2(GeH3)H] [24]
cis-[Ru(depe)2(GeH3)H] [24]
trans-[Ru(depe)2(GeH3)H] [24]
cis-[Ru(dmpe)2(GeH3)H] [24]
trans-[Ru(dmpe)2(GeH3)H] [24]
cis-[Ru(DuPhos)2(GeH3)H] 790.38 orthorhombic P212121 a 10.1222 b 18.4327 c 19.425 Z=4 3624.4 1.448 [24]
Ru(GeH3)(Cp′)L Cp′=η5-C5Me5 L=1,2-[bis(diphenyl) phosphanyloxy]-1,2-diphenylethane [25]
Ru(GeH3)(Cp′)L Cp′=η5-C9H7 L=1,2-[bis(diphenyl) phosphanyloxy]-1,2-diphenylethane [25]
Sb(GeH3)3 trigermylstibine [26]
Cs([18]crown-6)2GeH3 734.12 tetrahedral P4/n a=13.2513 c=19.0577 Z=4 3346.5 1.457 colourless [8]
CsGeH3 orthorhombic a=5.1675 b=14.435 c=5.9664 3.111 [10]
K[W(CO)5GeH3] [16][14]
[PPh4][W(CO)5GeH3] monoclinic C2/c a=22.227 b=7.025 c=18.529 β=96.11 Z=4 2883.2 1.71 yellow [14][15]
GeH3Re(CO)5 Germylpentacarbonylrhenium colourless mp 53-54°C [27]
GeH2[Re(CO)5]2 bis(pentacarbonylrhenium)germane [27]
Re(GeH3)(CO)2(PPh(OEt)2)3 white [4]
Re(GeH3)(CO)3(PPh(OEt)2)2 white [4]
Re(GeH3)(CO)2(P(OEt)3)3 white [4]
Re(GeH3)(CO)3(P(OEt)3)2 white [4]
K[Re(CO)25-C5H5)GeH3] [14]
[PPh4][Re(CO)25-C5H5)GeH3] [14]
Os(GeH3)(Tp)(PPh3)P(OMe)3 Tp = tris(pyrazolyl)borate white [23]

Related

Germylidyne with formula ≡GeH has a triple bond to the metal atom.[28]

Germylidene with base formula =GeH
2
has a double bond to the central metal.[29]

References

  1. Red Book. IUPAC. 2005. p. 298. 
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  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 Kraus, Charles A.; Carney, E. Seaton (April 1934). "Compounds of Germanium and Hydrogen: Some of their Reactions and Derivatives. I. Preparation of Monogermane. II. Sodium Trihydrogermanides". Journal of the American Chemical Society 56 (4): 765–768. doi:10.1021/ja01319a002. 
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