Activation of Methane and Toluene by Rhodium Porphyrin

Activation of Methane and Toluene by Rhodium(Ⅱ) Porphyrin Complexes Bradford B. Wayland*, Sujuan Ba, and Alan E. Sherry Date: 2016 -1 -23 1

Background u. Oxidative addition uσ -bond metathesis u. Addition to M=X groups Cummins, C. C. ; Baxter, S. M. ; Wolczanski, P. T. J. Am. Chem. Soc. 1988, 110, 8731 2

Reactions of (TMP)Rh 3

Thermodynamic and kinetic-mechanistic studies 4

Thermodynamic and kinetic-mechanistic studies Second order 5

Thermodynamic and kinetic-mechanistic studies 6

Reactions about benzene 7

Reactions of [(TXP)Rh]2 8

Thermodynamic and kinetic-mechanistic studies 9

Thermodynamic and kinetic-mechanistic studies 10

Reactions about benzene 11

Reactions of [(OEP)Rh]2 12

Reactions with toluene 13

Reactions about toluene 14

Reactions about toluene 15

Rh-Rh bond energy 16

Thermodynamic studies for methane activation M-M CH 3 -H (M-H)+(MCH 3) (TMP)Rh -13 0 105 118 [(TXP)Rh]2 0 12 105 117 Unit: kcal/mol (OEP)Rh-H 62 kcal/mol 17

Kinetic-mechanistic studies for methane activation • Obvious isotope effects • Small enthalpies 18

Kinetic-mechanistic studies for methane activation 19

Selectivity Rh(Ⅲ) react with Aromatic C-H Bond thermodynamically favored Rh(Ⅱ) no reaction with Aromatic C-H Bond kinetically inhibited 20

Overview • No reaction with aromatic C-H • React with alkyl C-H bonds • Two metalloradicals • Steric effect 21

The End Thank You! 22