Special relativity optical effects

Tertiary phosphines, in the absence of special effects 2 ), have relatively high barriers 8) ca. 30-35 kcal/mol) to pyramidal inversion, and may therefore be prepared in otically stable form. Methods for synthesis of optically active phosphines include cathodic reduction or base-catalyzed hydrolysis 3° 31) of optically active phosphonium salts, reduction of optically active phosphine oxides with silane hydrides 32), and kinetic 3 0 or direct 33) resolution. The ready availability of optically pure phosphine oxides of known absolute configuration by the Grignard method (see Sect. 2.1) led to a study 3 ) of a convenient, general, and stereospecific method for their reduction, thus providing a combined methodology for preparation of phosphines of known chirality and of high enantiomeric purity. 

However, no cells in the males were keyed to the third compound (- )-cubebene which is produced by the host tree. Both sexes of 5. scolytus possess a majority of receptor cells keyed to either of the two male-produced compounds, (-)-threo-4-methyl-3-heptanol and the (-)-erythro-stereo-isomer, and in this species some cells were keyed also to (- )- -multistriatin (Wadhams et al., 1982). The relative sensitivities and specificities of these cells were determined in the same way as described for Ips species. Each cell was minimally activated by pheromone components other than its own key substance. The functional types of olfactory receptor cells discussed here for Scolytus, as with the cells of Ips, apparently are all keyed to the specific isomer of the pheromone compounds. The cells specialized to (- )-a-multistriatin are 1000 times less sensitive to the geometrical isomer d-multistriatin. However, the discrimination of the optical form of multistriatin seemed to be less pronounced. The substantially lower effect of the (-l-)-stereo-isomer (optical purity 99.5%), cannot be solely ascribed to contamination with the (- )-enantiomer. It implies that these cells in fact may also respond to (-l- )-multistriatin, although to a lesser extent. The cells keyed to methyl-heptanol are, however, highly optically specific in both species. 

This behavior may be interpreted in terms of the operation of different solvation mechanisms snch as electronic polarizability, dipole density, and/or hydrogenbonding (HB) ability. For instance, the main physical difference between 71 and Ej(30), in the absence of HB interactions, is claimed to lie in different responses to solvent polarizability effects. Likewise, in the relationship between the 71 scale and the reaction field functions of the refractive index (whose square is called the optical relative permittivity ) and the relative permittivity, the aromatic and the halogenated solvents were found to constitute special cases.This feature is also reflected by the polarizability correction term ineqn. [12.1.1] below. For the selected solvents, the various polarity scales are more or less equivalent. An account of the various scales has been given by Marcus, and in particular of ti by Laurence et al. and of Ej by Reichardt. ... 

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