High-spin polycarbene

From High-spin Polycarbenes To Carbene-based Magnets... 

The chemistry of high-spin polycarbenes started in 1967 when two groups led by K. Itoh [1] and E. Wasserman [2] reported independently their findings that OT-phenylene-dicarbene Ic generated by the photolysis of diazo compound Id has a ground quintet state. Prior to this report, A. M. Trozzolo and coworkers... 

We designed six polydiazo compounds, 8- 13, which have partial structures of the honey-comb network 5. The array-shape, cyclic, and dendritic structures were expected to produce high-spin polycarbenes after irradiation. 

It is of interest to describe spin systems that are completely different from nitrox-ide-labeled dendrimers, but that also bear in their organic structure a high-spin multiplicity (with S > V) High-spin polycarbenes with ji-conjugation, which are the first and second generations of the spin-mediated dendrimers based on pheny-lacetylenes, were studied by a two-dimensional electron-spin transient nutation (2D-ESTN) method based on pulsed-ESR to determine the spin mulliphcity. The contour plots of the 2D-ESTN spectra of the dendrimer at 3.5 K allowed to identify the nutation frequencies, which were attributed to 4, 4> 4, 3>, 4, 3> <-> 4, 2>, 4, 2> 4, 1>, and 4, 1> 4, 0>. The ESR allowed the detec-... 

H. Iwamura, High-spin polycarbenes as models for organic ferromagnets. Pure Appl. Chem., 58, 187 (1986). 

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