Base-induced reversible H₂ addition to a single Sn(ii) centre

Area of Science:

• Organometallic Chemistry
• Main Group Chemistry
• Catalysis

Background:

• Oxidative addition (OA) of H2 is crucial in catalysis.
• Main group compounds offer unique reactivity.
• Frustrated Lewis pairs (FLPs) activate small molecules.

Purpose of the Study:

• To investigate amine-catalyzed OA of H2 to a low-valent tin compound.
• To elucidate the mechanism of H2 activation.
• To demonstrate reversible H2 activation at a main group center.

Main Methods:

• Experimental studies including kinetic isotope effect measurements.
• Computational studies (DFT) to explore reaction pathways.
• Spectroscopic characterization of intermediates and products.

Main Results:

• Various amines catalyze the OA of H2 to [(Me3Si)2CH]2Sn (1).
• Experimental and computational data support FLP mechanisms with late transition states.
• Reversible OA/reductive elimination (RE) of H2 was demonstrated using DBU.

Conclusions:

• Amine catalysis enables H2 activation by a main group tin compound.
• FLP-type mechanisms are involved in the observed H2 addition.
• The tin center can undergo reversible oxidative addition and reductive elimination of H2.