Heterodinuclear group 13 element complexes of an N 4 O 6 -type dipyrrin cyclic dimer were synthesized by the stepwise reaction with boron and group 13 elements (Al, Ga, and [a] NMR Spectroscopy: 1 H and 13 C NMR spectra were recorded on a Bruker AVANCE III-400 or 600 spectrometers. Tetramethylsilane was used as an internal standard (δ = 0.00 ppm) for 1 H and 13 C NMR measurements.Single-Crystal X-ray Diffraction: Single-crystal X-ray diffraction measurements were performed using a Bruker APEX II ULTRA with Mo-K α radiation (graphite-monochromated, λ = 0.71073 Å) at 120 K. The collected diffraction images were processed by Bruker APEX2. The initial structure was solved using SHELXS-2013 [49] and refined using SHELXL-2016, [50] which were running on Yadokari-XG crystallographic software. [51] CCDC 1848533 (for [LBGa(CH 3 OH) 2 ]), and 1848537 (for [LBIn(CH 3 OH) 2 ]) contain the supplementary crystallographic data for this paper. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre.Mass Spectroscopy: MALDI-TOF mass data were recorded on an AB SCIEX TOF/TOF 5800 system.
UV/Vis and Fluorescence Spectroscopy:UV-Vis spectra were recorded on a JASCO V-660 or V-670 spectrophotometer. Emission spectra were recorded on a JASCO FP-8600 fluorescence spectrophotometer. Absolute fluorescence quantum yields were determined with a Hamamatsu Photonics absolute PL quantum yield measurement system C9920-02. Solvents used for measurements were air-saturated.DFT Calculations: DFT calculations were carried out using the Spartan '16 software (Wavefunction, Inc. Irvine, CA). The geometry optimization of [LBGa(MeOH) 2 ] were performed at the B3LYP/6-31G(d) level. [52] Eur.