The regulation of multicolor fluorescence changes in mechanochromic fluorescence (MCF) remains a challenging task. Herein, we report the regulation of MCF using a donor‐acceptor structure. Two crystal polymorphs, BTD‐pCHO(O) and BTD‐pCHO(R) produced by the introduction of formyl groups to an MCF dye, respond to a mechanical stimulus, allowing a three‐color fluorescence change. Specifically, the orange‐colored fluorescence of the metastable BTD‐pCHO(O) polymorph changed to a deep‐red color in the amorphous‐like state to finally give a red color in the stable BTD‐pCHO(R) polymorph. This change occurred by mechanical grinding followed by vapor fuming. The two different crystal packing patterns were selectively regulated by the electronic effect of the introduced functional groups. The two types of selectively formed crystals in BTD(F)‐pCHO bearing fluorine atoms, and BTD(OMe)‐pCHO bearing methoxy groups, respond to mechanical grinding, allowing for the regulation of multicolor MCL from a three‐color change to two different types of two‐color changes.

Repetitive Mizoroki‐Heck (MH) coupling polymerization was used to create novel chiral polyureas with cinchona alkaloids in the main chain. Apart from two‐component polycondensation of cinchona urea dimers with diiodobenzene via MH reaction conditions, some chiral polyureas were easily polymerized under self polycondensation to yield the chiral polymers. The asymmetric Michael addition reaction was successfully carried out using chiral polymers derived cinchona urea. Interestingly, phenolic‐based chiral polymers served as heterogeneous catalysts for the enantioselective Michael reaction, with high catalytic activity and excellent enantioselectivities (up to 99 % ee). These polymeric catalysts were also stable, and they could be recycled and reused.