874299-61-3

Upstream product

• 205259-72-9 rhodium(III) tetrakis(4-tolyl)porphyrin chloride 
• 100-39-0 benzyl bromide 
• 103562-44-3 (5,10,15,20-tetrakis-4-tolylporphyrinato)rhodium(III) hydride 
• 100-51-6 benzyl alcohol 
• 946-80-5 (benzyloxy)benzene 
• 291-64-5 cycloheptane 
• 108-88-3 toluene 
• 352-32-9 p-fluorotoluene 
• 103533-61-5 (5,10,15,20-tetrakis-4-tolylporphyrinato)(methyl)rhodium(III) 
• 106-42-3 para-xylene 
• 106-43-4 para-chlorotoluene 
• 2037-26-5 ⁽²⁾H₈-toluene 
• 6140-17-6 4-methylbenzotrifluoride 
• 98-51-1 4-tert-butyltoluene 

Downstream Products

• 103562-44-3 (5,10,15,20-tetrakis-4-tolylporphyrinato)rhodium(III) hydride 
• 108-88-3 toluene 

Relevant academic research and scientific papers

Metalloradical-catalyzed rearrangement of cycloheptatrienyl to benzyl

Rh(ttp)(C7H7) rearranged to give Rh(ttp)(CH 2Ph) quantitatively at 120°C in 12 d (ttp = 5,10,15,20- tetratolylporphyrinato dianion). This process is 1010 faster than for the organic analogue. Mechanistic investi

Alkylation of Rhodium Porphyrin Complexes with Primary Alcohols under Basic Conditions

Primary alcohols were successfully utilized as the alkylating reagents to conveniently access rhodium porphyrin alkyl complexes in up to 91% yields under basic conditions. Mechanistic investigations suggest two possible pathways for the C-O bond cleavage: (1) nucleophilic substitution with rhodium(I) porphyrin anion and (2) a borrowing hydrogen pathway via rhodium(III) porphyrin hydride.

Alkyl Carbon-Oxygen Bond Cleavage of Aryl Alkyl Ethers by Iridium-Porphyrin and Rhodium-Porphyrin Complexes in Alkaline Media

Alkyl C-O bond cleavage in aryl alkyl ethers was achieved with Rh(ttp)Cl (1a; ttp = 5,10,15,20-tetrakis(p-tolyl)porphyrinato dianion) together with competitive alkyl C-H bond activation in alkaline media. In contrast, selective alkyl C-O bond cleavage occurred with the iridium-porphyrin Ir(ttp)(CO)Cl (1b)/KOH. Mechanistic investigations indicate the coexistence of MI(ttp)- and M2II(ttp)2 (M = Rh, Ir) under basic conditions. With a weaker Rh(ttp)-Rh(ttp) bond, RhII(ttp)· metalloradical exists in an appreciable amount to cleave the alkyl C-H bond, competing with the alkyl C-O bond cleavage via RhI(ttp)-. In contrast, the more nucleophilic IrI(ttp)- cleaves the alkyl C-O bond exclusively.

Facile Aerobic Alkylation of Rhodium Porphyrins with Alkyl Halides

Alkylation of rhodium porphyrins was achieved in moderate to high yields in the presence of air and water. With this facile alkylation method, various alkyl RhIII(por) species, including those with tertiary alkyl, were synthesized. Mechanistic

K2CO3-promoted consecutive carbon-hydrogen and carbon-carbon bond activation of Cycloheptane with rhodium(III) porphyrin complexes: Formation of rhodium porphyrin cycloheptyl and benzyl

K2CO3-promoted carbon-hydrogen and carbon-carbon bond activations of cycloheptane are achieved with rhodium(III) tetrakis(4-tolyl) porphyrin chloride (Rh(ttp)Cl) at 120 °C to give Rh(ttp) cycloheptyl and benzyl complexes. On the basis of mechanistic studies, Rh(ttp)Cl first reacts by ligand substitution to give Rh(ttp)OH, which then undergoes reductive elimination to give RhII2(ttp)2. The metalloradical RhII(ttp), formed via dissociation of Rh II2(ttp)2, activates the CH bond of cycloheptane to form Rh(ttp)(cycloheptyl) and Rh(ttp)H. Rh(ttp)(cycloheptyl) slowly yields Rh(ttp)(cycloheptatrieneyl) by successive β-hydride elimination to olefins and Rh(ttp)H. K2CO3 promoted the dehydrogenation of Rh(ttp)H to give RhII2(ttp)2 and H2. Both Rh(ttp)H and RhII2(ttp) 2 activate the cycloheptatriene to give Rh(ttp)(cycloheptatrienyl), which further undergoes a RhII(ttp)-catalyzed skeletal rearrangement to form Rh(ttp)Bn with rate enhancement much faster than that of the analogous organic isomerization of cycloheptatriene to toluene.

Base-promoted selective activation of benzylic carbon-hydrogen bonds of toluenes with rhodium(III) porphyrin chloride: Synthetic scopes and mechanism

Toluenes underwent base-promoted selective benzylic carbon-hydrogen bond activation (CHA) with rhodium porphyrin chlorides (Rh(por)Cl). In the absence of nucleophilic base, both aryl and benzylic rhodium porphyrins were formed. In the presence of nucleophilic base, the selectivity, rates and functional group compatibilities of benzylic activation reactions were enhanced. K 2CO3 was found to be the optimal base to achieve the best yields. Ortho-, meta- and para-substituted toluenes in the presence of K 2CO3 yielded the corresponding rhodium porphyrin benzyls in high yields both in solvent-free conditions and in benzene solvent. Mechanistically, in the absence of nucleophilic base, a cationic rhodium(III) porphyrin species together with some rhodium(II) porphyrin are the most likely intermediates to account both the aryl and benzylic CHA. In the presence of a base, Rh(por)OH is generated by ligand substitution with Rh(por)Cl and rapidly undergoes reduction to give rhodium(II) porphyin dimer and H2O 2. The key rhodium porphyrin intermediates for benzylic CHA were found to be rhodium(II) porphyrin dimer and hydrides as observed by 1H NMR spectroscopy, which underwent parallel benzylic CHA reactions with the rhodium(II) porphyrin dimer being the more reactive intermediate.

Selective activation of benzylic carbon-hydrogen bonds of toluenes with rhodium(III) porphyrin methyl: Scope and mechanism

Toluenes underwent selective benzylic carbon-hydrogen bond activation (BnCHA) with rhodium(III) porphyrin methyl. The ortho-, meta-, and para-substituted toluenes yielded the corresponding rhodium porphyrin benzyls in high yields in solvent-free conditions as well as in benzene solvent. Mechanistically, Rh(ttp)Me likely undergoes a σ-bond metathesis pathway. The small value of the kinetic isotope effect (2.7) indicates a bent transition state. The negative slope (-1.1) of the linear free energy relationship Hammett plot supports that the benzylic carbon builds up a positive charge in the transition state.

Syntheses of acyl rhodium porphyrins by aldehydic carbon-hydrogen bond activation with Rh(III) porphyrin chloride and methyl

Rhodium(III) porphyrin chloride reacted with aryl aldehydes in solvent-free conditions to give acyl rhodium porphyrins. Selective aldehydic without any aromatic carbon-hydrogen bond activation (CHA) was observed. At lower temperature, reduction and side products were found. Alkanals reacted poorly. On the other hand, Rh(III) porphyrin methyl reacted more cleanly with both aryl and alkyl aldehydes. These reactions provided a facile, convenient synthesis of acyl rhodium porphyrins. These activations are unique CHA by high-valent Rh(III) species. Preliminary mechanistic experiments suggested that the rhodium(III) porphyrin chloride initially formed a cationic rhodium(III) porphyrin via chloride dissociation and then underwent oxidative addition or heterolysis to yield the product. On the other hand, rhodium(III) porphyrin methyl underwent either oxidative addition or σ bond metathesis.