Abstract
Efficient and reliable synthesis of substituted hydrazinylpyridines in thick-wall
ACE tubes via nucleophilic substitution of a chlorine substituent in different chloropyridines
is presented. Hydrazine hydrate and alkylhydrazines were used as nucleophiles and
simple alcohols and diethyl ether were the only organic solvents necessary, making
the process environmentally and user friendly, potentially reaching 100% atomic efficiency.
In the next step, transformations of succinic anhydride moieties fused to the bicyclo[2.2.2]octene
framework into succinimide moieties via nucleophilic substitution of oxygens were
conducted. As nucleophiles two of the synthesized hydrazinylpyridines (2-hydrazinyl-3-nitropyridine
and 2-hydrazinyl-5-nitropyridine) and also hydrazine hydrate, phenylhydrazine, and
4-nitrophenylhydrazine were used. Reactions were again carried out in ACE tubes and
only simple alcohols, diethyl ether, and acetone were needed as solvents. One of the
prepared bicyclo[2.2.2]octene adducts displayed water solubility thus being a promising
candidate for future studies as a novel bidentate ligand for various metal cations
in aqueous solutions or acting as an unprecedented halogen bond acceptor.
Key words green chemistry - chloropyridine - bicyclo[2.2.2]octene - water-soluble ligand - succinimide
- nucleophilic substitution
