Cyclic aromatic system

Cooks, R.G. Howe, I. Tam, S.W. Williams, D.H. Studies in Mass Spectrometry. XXIX. Hydrogen Scrambling in Some Bi-cyclic Aromatic Systems. Randomization Over Two Rings. J. Am. Chem. Soc. 1968, 90,4064-4069. 

According to this procedure, with proper choice of reaction conditions, a sizeable amount of diphenylacetylene can be converted quantitatively to triphenyteyclopropenium bromide in a few hours. The reaction is of wide generality and can be applied to p-anisylphenylacetylene and to di-p-anisylacetylene, or with p-anisal chloride instead of a,a-dichlorotoluene. to prepare p-methoxy derivatives of the title compound.2 Since the initial preparation of this derivative of the cyclopropenyl cation by a less efficient procedure,3 many aryl-, alkyl- and heteroatom-substituted derivatives of this simplest cyclic aromatic system have been synthesized,4 including... 

Cyclic aromatic systems with hypervalent centers, in particular, heterapen-talenes 01CRV1247. 

The spectrum for naphthalene (C,oHg) is shown in Eigure 3.14. Spectra of other cyclic aromatic systems resemble the naphthalene spectrum, and this has stimulated development of theories, for example, those of Platt and Gouterman. 

The CH-activation can be combined with an intramolecular carbopalladation reaction to yield cyclic aromatic systems. In this case, indoles can be synthesized in an efficient manner (Experimental Procedure below). ... 

Cyclic Aromatic Systems with Hypetvalent Centers... 

Cyclic Aromatic Systems with Hypervalent Centers Scheme 4... 

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