Electron diffraction, allyl

The allyl radical would be expected to be planar in order to maximize n delocalization. Molecular structure parameters have been obtained from EPR, IR, and electron diffraction measurements and confirm that the radical is planar. ... 

Later, successful determination of the molecular structure of the free allyl radical was achieved by high-temperature electron diffraction, augmented by mass spectrometry studies (Vaida et al., 1986). The structural parameters obtained for the allyl radical were rcc 142.8 pm, rcH 106.9 pm, accc 124.6°, ccH 120.9°. This was the first electron diffraction study of an unstable organic molecule. 

F. Vanhouteghem, W. Pyckhout, C. Van Alsenoy, L. Van den Enden, and H. J. Geise, The molecular structure of gaseous allyl alcohol determined from electron diffraction, microwave, infrared and geometry relaxed ab initio data. J. Mol. Struct. 140, 33 48 (1986). 

The preparation of tropidinyl transition metal complex 53 was achieved by reaction of 4-trimethylstannyltropidine 52 with M(CO)sBr, M = Mn, Re <2003ZFAC2408>. In complex 53, the tropidinyl ligand is coordinated through the nitrogen and the three-carbon allylic system which serve as a 2o /47t-electron donor. It has been characterized by single-crystal X-ray diffraction analysis (Equation II). 

Stoichiometric experiments were conducted with the functionalized alkenes to further explore iron-substrate interactions and gauge relative coordination affinities. Several bis(imino)pyridine iron amine and ketone compounds were isolated and studied using a combination of X-ray diffraction, NMR and Mossbauer spectroscopy and established electronic structures similar to that for ( PDI)Fe(N2)2-In the absence of H2, diallyl ether and allyl ethyl ether underwent facile C-0 bond cleavage and yielded a near equimolar mixture of the corresponding iron allyl and alkoxide complexes [89]. Our group has recently published a comprehensive study on these types of reachons and discovered rare examples of C-0 bond cleavage in saturated esters [89]. 

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