Showing papers by "Lawrence B. Alemany published in 2002"
TL;DR: Measurements of 13C nu(1/2) and T(1) values on tripalmitin provide secure assignments for the C-5 and C-6 signals, for which conflicting assignments have been reported, and show that among the tightly clustered C-8 through C-12 signals, theC-11 signals are the most downfield, while the C -12 signals areThe most upfield, contrary to a previous report.
23 citations
TL;DR: Ab initio calculations indicated that the two strained olefins 1a and 5 had comparable energies about 50 kcal/mol lower than norborna-1(7),2,5-triene, which was thus excluded as a reaction intermediate.
Abstract: Thermolysis of spiro[2.4]hepta-1,4,6-triene (1a) at 50 °C yielded bicyclo[3.2.0]hepta-1,3,6-triene (5), which dimerized in two different fashions to form cyclobutanes. The 1,2-dimethyl and 1-propyl derivatives of 1a also rearranged at 50 °C, but at a faster rate, each yielding a pair of cyclobutane dimers. The structures of these symmetrical dimers were investigated by 1D and 2D NMR and NOE difference spectroscopy. Ab initio calculations indicated that the two strained olefins 1a and 5 had comparable energies about 50 kcal/mol lower than norborna-1(7),2,5-triene, which was thus excluded as a reaction intermediate.
13 citations
TL;DR: In this article, the synthesis and characterization of fullerene hydrides from C60 and C70 are discussed, particularly MS and NMR, including 3He nuclear magnetic resonance spectroscopy.
Abstract: The syntheses and characterization of fullerene hydrides prepared from C60 and C70 are reviewed. Methods of isolation and characterization are discussed, particularly MS and NMR, including 3He nuclear magnetic resonance spectroscopy. The higher hydrides are discussed in terms of novel structural features and their unusual spectroscopic properties.