10.1021/jo001737+
The research focuses on the synthesis of (-)-delobanone, a sesquiterpene, using a novel approach that involves the preparation of alkenyl cyclopropane 2 from the Sharpless-derived epoxide 1. The key reactants include geraniol, which undergoes Sharpless epoxidation to form an epoxide, followed by sulfonylation to produce benzenesulfonate 11. This is then reacted with lithioacetonitrile to yield nitrile 9, which is further transformed into aldehyde 8 through a DIBAL-H reduction. The aldehyde is converted into an alkenyl cyclopropane 2 via a Wittig reaction. The final step involves the irradiation of 2 in the presence of Fe(CO)5 under a CO atmosphere to achieve the ring expansion, resulting in (-)-delobanone 3. Throughout the synthesis, various analytical techniques were employed, including NMR, IR, MS, and optical rotation measurements, to monitor the progress and confirm the structures of the intermediates and final product. The research also discusses the potential challenges and the successful optimization of the reaction conditions to achieve high yields and selectivity.
10.1021/ja902420u
The research investigates the self-assembly behavior of positively charged polycyclic aromatic hydrocarbons (PAHs) into columnar superstructures, which have potential applications in organic (opto)electronics and nanotechnology. The study focuses on a class of ionic complexes based on 9-phenylbenzo[1,2]quinolizino[3,4,5,6-fed]phenanthridinylium (PQP) ions. The researchers discovered that the organization of these complexes into columnar structures can be controlled by varying the organic counterions. Specifically, the use of sulfonate anions with long alkyl tails led to well-ordered discotic columnar mesophases. Benzenesulfonate anion was used in the PQP complex (compound 2) to form a columnar structure in the crystal. The study utilized various techniques, including single-crystal X-ray diffraction and fiber wide-angle X-ray scattering (WAXS), to analyze the structures and properties of the PQP complexes. The findings suggest that the columnar organization of these ionic complexes can be easily tuned by their counterions, opening up possibilities for further adjustments through the use of more elaborate counterions. The research concludes that these materials hold promise for applications in 1D anisotropic ion transport and the construction of novel charge-transfer complexes.
