Un. Alexander et al., Temperature dependence of germylene reactions with acetylene, trimethylsilane, and phenylgermane, CHEM P LETT, 319(5-6), 2000, pp. 529-534
Gas-phase reaction rate constants have been determined over the temperature
range 295-436 K for the reactions of germylene, GeH2, with acetylene (GeH2
addition across a triple bond), trimethylsilane (GeH2 insertion into a Si-
H bond), and phenylgermane. The room-temperature rate constant for germylen
e reacting with benzene has been measured and is found to be a factor of si
milar to 300 smaller than that for phenylgermane, indicating that the latte
r reacts by GeH2 insertion into the Ge-H bonds. A negative temperature depe
ndence is observed in all cases. The activation energies, obtained from wei
ghted linear fits to the data over the experimental temperature range, are
- 3.5 +/- 0.3, - 11.0 +/- 0.4, and - 3.6 +/- 0.3 kJ mol(-1) for acetylene,
trimethylsilane, and phenylgermane, respectively, while the respective freq
uency factors, log( A/cm(3) molecule(-1) s(-1)), are - 10.5 +/- 0.1, - 11.8
+/- 0.1, - 10.1 +/- 0.1. (C) 2000 Elsevier Science B.V. All rights reserve
d.