Figure 2. Synthesis of donor–acceptor cruciform-like molecules.

The initial step is a Wittig reaction, which is followed by a one-pot transesterification and desilylation. The terminal alkyne product is subjected to a Sonogashira reaction, furnishing the molecular wire with thioacetate end groups. The last step is a Knoevenagel condensation. Me, methyl; Et, ethyl; Pr, propyl; Bu, butyl; Ac, acetyl; Ph, phenyl; THF, tetrahydrofuran; rt, room temperature.