We are interested in atoms that break The Rule. In exceeding their valence octets, these scofflaws are in violation of the Octet Rule, and are termed "hypervalent." Hypervalent systems based on sulfur, phosphorus, iodine, and other main group elements in the third row or lower of the periodic table are numerous. By contrast, examples of hypervalent boron, carbon, and other second row elements are rare. We are exploring the possibility of preparing an isolable example of hypervalent nitrogen.
The gist of our idea for doing this, 1, is pictured below. Depending on the nature
of L, the system may be neutral or charged. Some systems which have been explored in a preliminary way are Z = O, L = B, and Z = O, L = Si-R. We are also preparing systems in which Z = N-R, where R is a bulky group. In synthesizing 1, we also are able to generate 2, which, after elaboration, may be useful as a host molecule in host-guest interactions.
We are also heading in a new direction. Hexaol 3 is previously unknown. One way to view it is as two molecules of glycerol attached at C2. It will be interesting to see what novel “double triglycerides” can be prepared from 3. Also, oxidation of one ‑CH2OH group of 3 to an aldehyde yields an isomer of glucose, which might be expected to exist in the pyranose form, 4. As such, it might be used in the synthesis of unnatural nucleosides. Finally, 3 may serve as a rare AB6 core for dendrimer construction.
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M. Yang, M.; T. Albrecht-Schmitt, T.; Cammarata, V.; Livant, P.; Makhanu, D. S.; Sykora, R.; Zhu, W. “Trialkylamines More Planar at Nitrogen Than Triisopropylamine in the Solid State.” J. Org. Chem. 2009, 74, 2671-2678.
Ji, X.; Khan, J. A.; Mosjidis, J. A.; Wang, H.; Livant, P. “Variability for the Presence of Pyrrolizidine Alkaloids inCrotolaria juncea L.“ Pharmazie 2005, 60, 620-622.
Livant, P.; Jie, Y.; Wang, X. “A Carbenoid N-H Insertion Route To Some Triarylamines via 2-Diazo-1,3-Cyclohexanedione.” Tetrahedron Lett. 2005, 46, 2113-2116.
P. Livant, P.; Northcott, D. J. D.; Shen, Y.; Webb, T. R. “Bonding Along a Linear B···N···B Triad.” J. Org. Chem.2004, 69, 6564-6571.