Asymmetric induction of n4-iron diene complexes.
The use of tricarbonyliron chemistry in asymmetric synthesis is of increasing
importance. With this comes the need for efficient and reliable techniques for the
production of enantiopure starting materials. The methods currently available,
although effective, are often long winded and wasteful. The development of a chiral
hydride abstraction reagent analogous to the triphenylcarbenium species would be of
great value in terms of improved yields and simplification of strategy.
This thesis details the development of a system based around the dibenzosuberane
frame-work. Two different chiral biases have been introduced to the structure leading
to a potential double stereodifferentiation effect. Substitution of the 'backbone' of the
structure has yielded enantiomeric excesses of up to 54%. The smaller, chiral aryl
bias has given e.e.s in the region of 10%. Moreover the synthetic route to the
backbone substituted examples has been greatly improved and is now suitable for use
on a multigram scale.