The bulky primary phosphane 2,6-diisopropylphenylphosphane, DipPH2, has been prepared from 1-bromo-2,6-diisopropylbenzene via the reaction of the Grignard reagent with PCl3. The resulting mixed phosphonous dihalides DipP(Cl,Br)2 are reduced with LiAlH4 to yield the title compound in reasonable yield and on a synthetically useful scale. DipPH2 is also used to prepare the monosilylated derivatives DipPHSi(CH3)3 and DipPHSi(CH3)2-t-Bu} as well as the disilylated compounds DipPSi(CH3)3}2 and DipPSi(CH3)2-t-Bu}2. All products have been fully characterized by IR, mass, and NMR spectroscopy. The crystal structure of DipPHSi(CH3)2-t-Bu} was determined from single-crystal diffraction data: C18H33PSi, P21/c, Z = 4, a = 8.5768(10), b = 28.104(3), c = 8.1102(4) Å, β = 93.341(3)° (R = 0.0518). Changes in the NMR spectrum of DipPHSi(CH3)2-t-Bu} were observed over the temperature range 178380 K. Barrier heights were determined from the peak separation at low temperature and the coalescence points: ΔG [Formula: see text] 40 kJ mol1 for C(aryl)P bond rotation and [Formula: see text] 72 kJ mol1 for pyramidal inversion at phosphorus.Key words: crystal structure, 2,6-diisopropylphenyl, bulky substituents, steric congestion, dynamic NMR, primary phosphane, silyl phosphane.