Metal-free, magnesium, titanyl, and vanadyl tetrapyrazinoporphyrazines substituted with eight 2,6-diisopropylphenoxy groups at the peripheral positions were prepared and characterized by NMR, UV-Vis, magnetic circular dichroism (MCD), and mass spectrometry methods. In addition, the Pc(2,6iPrPhO)8VO complex was characterized by EPR spectroscopy and X-ray crystallography. Reaction between TiCl4with 4,5-(2,6-diisopropylphenoxy)phthalonitrile in N,N-dimethylaminoethanol resulted in the formation of a red open-chain trimer, which was characterized by mass spectrometry and X-ray crystallography. Electronic structures of new compounds and their excited state properties were probed by Density Functional Theory (DFT) and Time-Dependent DFT (TDDFT) methods.
2‐Formylphenylboronic acid condenses with active methylene reagents like α‐amino esters, ketones, and lactams directly to give benzo‐fused 1‐hydroxy‐2,1‐azaborines in good yields within minutes under microwave‐accelerated conditions. The new stable boron heterocycles prepared to demonstrate this approach were characterized by NMR spectroscopy. Three members of a new diboron heteropentacyclic ring system, 5a,12a‐diaza‐5,12‐dibora‐5,12‐dihydroxypentacene‐6,13‐dione, were prepared, and one of these highly fluorescent compounds was characterized by X‐ray crystallography. Some key solid‐state structural features revealed by the X‐ray analysis provide a basis for explaining the limited solubility of these pentaheterocycles in common organic solvents.
more » « less- NSF-PAR ID:
- 10372700
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Heterocyclic Chemistry
- Volume:
- 56
- Issue:
- 10
- ISSN:
- 0022-152X
- Page Range / eLocation ID:
- p. 2960-2965
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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