ROOM-TEMPERATURE STABLE GROUND-STATE TRIPLET CARBENE WITH PERPENDICULAR CONFORMATION AS MODELS FOR ORGANIC HIGH-SPIN UNITS WITH ROBUST PI-SPIN POLARIZATION

A ground-state tripler diphenylcarbene derivative, 2,2',4,4',6,6'-hexa bromodiphenylcarbene 2 was synthesized and generated to be a model for chemically stable organic high-spin molecules. This paper describes E SR detection of 2 in the crystal of the diazo precursor 1 and the mole cular and crystal structure of the diazo precursor obtained by X-ray d iffraction at room temperature. The crystal is monoclinic with cell di mensions, a=9.993 Angstrom, b=13.261 Angstrom, c=12.743 Angstrom, thet a=91.88 degrees, Z=4, and the space group P2(1)/n. The two phenyl ring s of 2,4,6-bromo-substitution make bent perpendicular conformation wit h 139 degree of the bond angle at the diazo methane, Non-bonded contac ts shorter than the van der Waals radii were found between the nitroge n and bromine atoms of the nearest neighboring molecules.