Synthesis of Photoactive Compounds

N₃–TEG–OTs 2(32 (link)) and chlorin e6–DME 4(34 (link)) were prepared according to
the literature. Mal₃ (Sigma-Aldrich, >90%), PA (Tokyo
Chemical
Industry Co., Japan, >95.0%), CuSO₄ (Wako Pure Chemical
Industries, Japan, 97.5%), sodium L-ascorbate (Wako Pure Chemical
Industries, Japan, 98.0%), Cs₂CO₃ (Tokyo Chemical
Industry Co., Japan, >98%), tert-butyl alcohol
(Tokyo
Chemical Industry Co., Japan, >99.0%), and dry N,N-dimethylformamide (Wako Pure Chemical Industries,
Japan,
99.5%) were used as received. All other materials were obtained from
commercial sources and used as received, unless otherwise stated.