Carbene transfer reactivity from a nickelacyclobutane

Area of Science:

• Organometallic Chemistry
• Organic Synthesis
• Computational Chemistry

Background:

• Nickelacyclobutanes are typically considered intermediates in catalytic cyclopropanation reactions.
• The reactivity of isolated nickelacyclobutanes beyond cyclopropanation is less explored.
• Carbene transfer reactions are fundamental in organic synthesis.

Purpose of the Study:

• To report a novel carbene-transfer reaction involving an isolated nickelacyclobutane.
• To investigate the reaction mechanism between nickelacyclobutanes and isocyanides.
• To explore the potential of nickelacyclobutanes as carbene reservoirs.

Main Methods:

• Isolation of a nickelacyclobutane complex.
• Reaction of the nickelacyclobutane with an isocyanide.
• Density Functional Theory (DFT) calculations to elucidate the reaction pathway.

Main Results:

• Successful carbene transfer from nickelacyclobutane to isocyanide, yielding a ketenimine.
• DFT calculations indicate a stepwise 1,1-insertion/fragmentation mechanism.
• Absence of a discrete carbene intermediate in the proposed pathway.

Conclusions:

• Nickelacyclobutanes can serve as carbene reservoirs in reactions with isocyanides.
• The observed reactivity expands the known chemistry of nickelacyclobutanes.
• The findings suggest a new synthetic utility for these organometallic compounds.