Synthesis and photophysical properties of novel pyridine fused chlorophyll a derivatives

Synthesis, Optical Properties and DNA‐Binding Behavior of a Quinoxaline Ring‐Fused π‐Elongated Chlorin – Efforts Towards Preparation of Long Wavelength Absorbing Porphyrinoids

“…[33] This molecule possessed a split Soret band at 413 and 442 nm and a sharp chlorin-like Q y -band at 651 nm (Table 1). The spectrum was similar in profile and Q-band position to two other types of well-known nickel (II) tetraphenyl chlorins, comprising of a non-pyrrolic morpholine or a saturated pyridone subunit, prepared by Brückner et al [30,34] It must be noted that free base benzochlorins derived from chlorophyll a do exist in the literature, [35] but similar free base chlorins derived from purely synthetic meso-tetraryl porphyrins are yet to be seen. In order to address these shortcomings and inspired by the recent developments in the synthesis of metallobenzochlorins, we set out to investigate the following question.…”

“…It must be noted that free base benzochlorins derived from chlorophyll a do exist in the literature, [35] but similar free base chlorins derived from purely synthetic meso‐ tetraryl porphyrins are yet to be seen. In order to address these shortcomings and inspired by the recent developments in the synthesis of metallobenzochlorins, we set out to investigate the following question.…”

Recent Advances in Heterocyclic Nanographenes and Other Polycyclic Heteroaromatic Compounds

“…In a recent example, pyridine-fused chlorins such as 358.2 were elaborated via conventional condensation chemistry ( Scheme 358 ). 676 In the final step, 358.1 was reacted with ammonium acetate in acetic acid to close the heterocyclic ring. These pyridine fused chlorophylls showed significant bathochromic shifted absorption in the near-infrared region (748–766 nm) with unusually broadened Q bands, as well as small electrochemical HOMO–LUMO gaps (1.89–2.02 eV).…”

Substituted Methylenation at the 132‐Position of a Chlorophyll‐a Derivative via Mixed Aldol Condensation, Optical Properties of the Synthetic Bacteriochlorophyll‐d Analogs, and Self‐aggregation of Their Zinc Complexes†

“…Methylenation the 13 2 -position (Y = H 2 to CH 2 in Fig. 1C) in methyl pyropheophorbide-a (R 3 = vinyl) led to red shifts of the Soret and Qy band because of the direct conjugation of an ethenyl moiety at the 15-position in a chlorin p-skeleton (47). Similar bathochromic shifts were found in the related 3-substituted chlorins: R 3 = Et (24), CH 2 OH (48), and CH(OH)Me (49).…”