EMME

Ravenek W and Geurts EMM 1986 Hartree-Fock-Slater-LCAO implementation of the moderately large-embedded-cluster approach to chemisorption. Calculations for hydrogen on lithium (100) J. Chem. Phys. 84 1613-23... 

The location of the quantum/classical boundary across a covalent bond also has implications for the energy terms evaluated in the Emm term. Classical energy terms that involve only quantum atoms are not evaluated. These are accounted for by the quantum Hamiltonian. Classical energy terms that include at least one classical atom are evaluated. Referring to Figure 2, the Ca—Cp bond term the N — Ca—Cp, C — Ca—Cp, Ha— Ca—Cp, Ca—Cp — Hpi, and Ca—Cp — Hp2 angle tenns and the proper dihedral terms involving a classical atom are all included. 

Here emm is the energy of the MM part of the system, and this is calculated from a straightforward MM procedure. qm is the quantum-mechanical energy of the solute and, in recent years, different authors have used semi-empirical, ab initio and density functional treatments for this part. The mixed term represents the interactions between the MM atoms with the quantum-mechanical electrons of the solute, as well as the repulsions between the MM atoms and the QM atomic nuclei. 

In 1939, Gould and Jacobs reported the condensation of aniline with acetyl malonic ester (AME) and ethoxymethylenemalonate (EMME), respectively, followed by cyclization of anilinomethylenemalonic ester 13 and 14 in mineral oil to afford the esters 15 and 16. Saponification of the esters gave the known acids 17 and 18, respectively. 

Due to the commercial availability of EMME in good purity, there has not been a need to develop new methods to prepare 3-anilino-acrylates therefore, only a few alternatives have been reported. One approach described thermal carbene generation from 37, and rearrangement to form 38. Cyclization in refluxing 1,2-dichlorobenzene (1,2-DCB) provided the 2, 3, 4-trisubstituted quinolines. An electron-withdrawing group (EWG) on the carbene carbon was required for this reaction, and therefore led to the EWG substitution in the 2-position of the quinoline. 

A mixture of aniline 131 (20 mmols) and EMME (22 mmols) was warmed to 100 °C for 80 min with a light N2 flow to remove the ethanol which was formed. Hexanes was added and the reaction mixture warmed and allowed to cool to rt to give malonate 132 as a slightly pink solid in 85% yield. For malonate 132 mp = 76-77 °C IR (KBr) 1739... 

The viscosities of non-haloaluminate ionic liquids are also affected by the identity of the organic cation. For ionic liquids with the same anion, the trend is that larger allcyl substituents on the imidazolium cation give rise to more viscous fluids. For instance, the non-haloaluminate ionic liquids composed of substituted imidazolium cations and the bis-trifyl imide anion exhibit increasing viscosity from [EMIM], [EEIM], [EMM(5)IM], [BEIM], [BMIM], [PMMIM], to [EMMIM] (Table 3.2-1). Were the size of the cations the sole criteria, the [BEIM] and [BMIM] cations from this series would appear to be transposed and the [EMMIM] would be expected much earlier in the series. Given the limited data set, potential problems with impurities, and experimental differences between laboratories, we are unable to propose an explanation for the observed disparities. 

Jansen JFGA, de Brabander-van den Berg EMM, Meijer EW (1994) Science 266 1226... 

Newman DK, EK Kennedy, JD Coates, D Ahmann, DJ Ellis, DR Lovley, EMM Morel (1997) Dissimilatory arsenate and sulfate reduction in Desulfotomaculum auripigmentum sp. nov. Arch Microbiol 168 ... 

Acknowledgements The authors would hke to thank the Spanish Ministeiio de Ciencia e Innovacion (EMM) and the EPSRC (MJP) for financial support. 

Mason RP, Reinfelder JR, Morel EMM. 1996. Uptake, toxicity, and trophic transfer of mercury in a coastal diatom. Environ Sci Technol 30 1835-1845. 

Read, Bernard Emms. Chinese alchemy. Chinese Med Hist Soc 5th anniversary special number (1931 (1941 )). 

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