Novel strategies for the construction of cyclic boronate esters and acids & novel aspects of furan chemistry

Methodology studies for cyclic boronate ester synthesis Figure i: Target molecules (see Abstract in pdf for image) Structures i,ii,iii represent a general depiction of cyclic boron-containing heterocyles targeted in this methodology study. These molecules will be made using a range of new organic pathways. A 1,3 nitrogen-boron relationship in selected structures will also be investigated due to its importance in pharmaceutical chemistry. In the pursuit of cyclic boranes a new method for the preparation of unsaturated ketones has been discovered, which utilises the boron chemistry outlined below. Figure ii: Reagents and Conditions: (a) tBuLi, B(OIPr)3, Et2O, -79 °C, 20 % (see Abstract in pdf for image) Novel aspects of furan chemistry It was found that the furan derivative vii, when treated with palladium salts, gave the bis-annulated benzene structure viii. This sequence gave rise to a novel method for the construction of aromatic rings. This reaction was tested on a range of substituted furans in order to examine the scope of this reaction. Figure iii: Reagents and Conditions: (a) Pd(OAc)2, K2CO3, MeCN, 80 °C, 25% (see Abstract in pdf for image)