Toward an Improved Understanding of the Unusual Reactivity of Pd(0)/Trialkylphosphine Catalysts in Cross-Couplings of Alkyl Electrophiles. I. Quantifying the Factors that Determine the Rate of Oxidative Addition

All reactions were carried out under an atmosphere of nitrogen or argon in oven-dried glassware with magnetic stirring, unless otherwise indicated. Toluene and THF were purified by passage through a neutral alumina column, and t-amyl alcohol was purified by distillation from CaH2. All other solvents were used as received: hexane (Aldrich; Sure/Seal); NMP (Aldrich; Sure/Seal); DMF (Aldrich; Sure/Seal). All alkyl halides were purified by either distillation or vacuum transfer: n-nonyl iodide (Aldrich); n-nonyl bromide (Aldrich); n-nonyl chloride (Aldrich); n-nonyl fluoride (Aldrich); 1-bromo-3-methylbutane (Aldrich); isobutylbromide (Aldrich); isopropylbromide (Aldrich). n-Nonyl tosylate was prepared by tosylation of n-nonyl alcohol. P(t-Bu)2Me (Strem) and Pd(P(t-Bu)3)2 (Strem) were used without further purification. Pd(PCy3)2 (Strem) was purified by recrystallization from toluene/methanol. P(t-Bu)2Et was prepared as previously described.[1] 1H and 13C NMR resonances are referenced to the solvent. 31P NMR resonances are referenced to external 85 % H3PO4. 2 II. Preparation of PdL2 Complexe