Carbenoid
In
complex
that takes the form of
- I-CH2-Zn-I
This complex reacts with an alkene to form a cyclopropane just as a carbene would do.
Carbenoids appear as intermediates in many other reactions. In one system a carbenoid chloroalkyllithium reagent is prepared in situ from a sulfoxide and t-BuLi which reacts the boronic ester to give an ate complex. The ate complex undergoes a 1,2-metallate rearrangement to give the homologated product, which is then further oxidised to a secondary alcohol.[2]
The
enantiopurity of the chiral sulfoxide is preserved in the ultimate product after oxidation of the boronic ester to the alcohol
indicating that a true carbene was never involved in the sequence.
See also
- The silicon pendant: Silylenoids
References
- ISBN 0-534-07968-7