Tetraphenylethene-based tetracationic dicyclophanes: synthesis, mechanochromic luminescence, and photochemical reactions

Two tetraphenylethene-based tetracationic dicyclophanes 1 and 2 were synthesized via a one-step S N 2 reaction. Based on the central TPE unit and the slight difference of the outer linkers, 1 and 2 exhibited a classic aggregation-induced emission but contrasting mechanochromic luminescence under grinding, vaporing, or hydrostatic pressure in the solid state, and photochemical reactions with various emitting colours induced by photoirradiation in the solution state. Two TPE-based tetracationic dicyclophanes 1 and 2 exhibited a classic AIE but contrasting mechanochromic luminescence under grinding or hydrostatic pressure in solid state, and photochemical reactions induced by photoirradiation in solution state.