Metal-free synthesis of 1H-isochromenes via benzyl ether-assisted, electrophilic addition of diaryl acetylenes

Bromotrimethylsilane (TMSBr) promoted, intramolecular cyclization of (o-arylethynyl)benzyl ethers to form 1H-isochromenes at room temperature is reported. Further studies indicated that the stability of vinyl carbocations is crucial, similar to the...

Diels-Alder Additions as Mechanistic Probes–Interception of Silyl-Isoindenes: Organometallic Derivatives of Polyphenylated Cycloheptatrienes and Related Seven-Membered Rings

The intermediacy of short-lived isoindenes, generated in the course of metallotropic or silatropic shifts over the indene skeleton, can be shown by Diels-Alder trapping with tetracyanoethylene, leading to the complete elucidation of the dynamic behaviour of a series of polyindenylsilanes. Cyclopentadienones, bearing ferrocenyl and multiple phenyl or naphthyl substituents undergo [4 + 2] cycloadditions with diaryl acetylenes or triphenylcyclopropene to form the corresponding polyarylbenzenes or cycloheptatrienes. The heptaphenyltropylium cation, [C7Ph7+], was shown to adopt a nonplanar shallow boat conformation. In contrast, the attempted Diels-Alder reaction of tetracyclone and phenethynylfluorene yielded electroluminescent tetracenes. Finally, benzyne addition to 9-(2-indenyl)anthracene, and subsequent incorporation of a range of organometallic fragments, led to development of an organometallic molecular brake.

Ni-Catalyzed electrophile driven regioselective arylative cyclization of ortho-functional diaryl acetylenes for the synthesis of pyridine and indene derivatives

A regioselective arylative cyclization of ortho functional diaryl acetylenes for the synthesis of selectively substituted diaryl pyridine and indene derivatives is accomplished through an electrophile driven alkyne polarization.

Synthesis of novel natural product-like diaryl acetylenes as hypoxia inducible factor-1 inhibitors and antiproliferative agents

A series of selaginellin analogues, biphenyl-containing diaryl acetylenes, were synthesized and evaluated for their cytotoxic and HIF-1 inhibitory activities.