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The styryl dehydro-Diels–Alder reaction with a conjugated diyne is reported. While typical alkyne–styrene condensation requires elevated temperatures (>160 °C), the application of a conjugated diyne allowed for effective transformation under milder conditions (80 °C). The thermally stable triazole–gold (TA–Au) catalyst further improved the reaction yields (up to 95%), producing the desired alkynyl–naphthalene in a single step with molecular oxygen as the oxidant. Sequential alkyne activation resulted in various polyaromatic hydrocarbons (PAHs) in excellent yields, highlighting the efficiency of this new strategy for the preparation of PAHs with good functional group tolerance and structural diversity. 

Systematic investigations were performed with various substituted groups at C8 purine and ribose. A series of isoG analogs, C8-phenyl substituted isoG were synthesized and applied for Cs + coordination. The structural proximity between purine and ribose limited pentaplex formation for C8-phenyl substituted isoG derivatives. Based on this observation, deoxy isoG derivative with modification on ribose ( tert -butyldimethylsilyl ether) was applied to assemble with the Cs + cation. Critical solvent (CDCl 3 and CD 3 CN) and anion (BPh 4 − , BARF − , and PF 6 − ) effects were revealed, leading to the controllable formation of various stable isoG pentaplexes, including singly charged decamer, doubly charged decamer, and 15-mer, etc. Finally, the X-ray crystal structure of [isoG 20 Cs 3 ] 3+ (BARF − ) 3 was successfully obtained, which is the first example of multiple-layer deoxy isoG binding with the Cs + cation, providing solid evidence of this new isoG ionophore beyond two-layer sandwich self-assembly.