s-Triazine as an exchange linker in organic high-spin molecules

Cobalt(II) Terpyridin-4′-yl Nitroxide Complex as an Exchange-Coupled Spin-Crossover Material

“…The latter was subjected to the preparation of tpyphNO (Scheme 2), as follows. The counterpart 4-(N-tert-butyl-O-tert-butyldimethylsilylhydroxylamino)phenyl boronic acid (TBDMS-BA) was prepared according to the literature method [29]. A mixture of Br-tpy (730 mg; 2.34 mmol), TBDMS-BA (741 mg; 2.30 mmol), Pd(PPh 3 ) 4 (271 mg; 0.24 mmol), Na 2 CO 3 (2.50 g; 14.3 mmol) in 50 mL of dioxane and 50 mL of water was heated at 100 • C for 72 h. The resultant mixture was extracted with dichloromethane, washed with brine and dried over anhydrous Na 2 SO 4 .…”

“…A new ligand tpyphNO was prepared via the Suzuki coupling reaction [32] from commercially available 4 -bromoterpyridine (Br-tpy) and a protected hydroxylaminophenyl boronic acid (TBDMS-BA) [29] (Scheme 2a). Paramagnetic tpyphNO was prepared after the deprotection of the above product with tetrabutylammonium fluoride followed by the oxidation with Ag 2 O.…”

Recent applications of the Suzuki–Miyaura cross-coupling reaction in organic synthesis

“…176 s-Triazines are effective ferromagnetic exchange linkers for p-(t-butylnitroxylphenyl) and p-phenoxyl groups. 177 The central triazine core promotes planarity in the solid state for attached phenyl groups in comparison to the non-planar geometry found in systems with a central benzene core. In this regard, the trinitroxide 150 was prepared from cyanuric chloride using the SM cross-coupling reaction.…”

Tuning the position of unpaired electrons and doublet–quartet gap of the 1,3,5-trimethylenebenzene triradical by nitrogen, phosphorus and arsenic substitution

“…1,3,5-Triaminobenzene (TAB) and 1,3,5-triaminotriazine (TATA) are important building blocks in the preparation of high-spin polycation polyradicals [13][14][15][16], and 1,3,5-triaminobenzene trication triradical (Scheme 1, TAB 3+ ) provides the simplest model for these polyradicals. Electron spin resonance experiments and multi reference multi state MS-CASPT2 quantum chemical computations suggest that this trication also has a D 3h symmetry, high-spin 4 A 00 2 ground state, and the corresponding low spin 2 A 2 and 2 B 1 states are lying 35.1 and 33.0 kJ/mol above the ground state, respectively.…”