Correlation configuration

Seetion treats the spatial, angular momentum, and spin symmetries of the many-eleetron wavefunetions that are formed as anti symmetrized produets of atomie or moleeular orbitals. Proper eoupling of angular momenta (orbital and spin) is eovered here, and atomie and moleeular term symbols are treated. The need to inelude Configuration Interaetion to aehieve qualitatively eorreet deseriptions of eertain speeies eleetronie struetures is treated here. The role of the resultant Configuration Correlation Diagrams in the Woodward-Hoffmann theory of ehemieal reaetivity is also developed. 

A. Plots of CSF Energies Give Configuration Correlation Diagrams... 

Configuration correlation diagram for homonuclear case in which homolytic bond cleavage is energetically favored. 

A somewhat similar configurational correlation between (leva)-glyceraldehyde and (dexfro)-lactic acid has been made by Wolfrom, Lemieux, Olin and Weisblat.36 Reductive desulfurization of tetra-acetyl-2-methyl-D-glucose diethyl thioacetal (XXVII) and hydrolysis of the product gave 2-methyl-l-desoxy-D-glucitol (XXVIII) oxidation... 

Historically, (/2)-(+)-a-NEA served as the CSA for the first configurational correlations made by the NMR-CSA method (30). Thirteen enriched alkylarylcarbinols were examined the carbinyl proton resonances of enantiomers with stereochemistry 27 were observed at... 

Nevertheless, correlations have been found in four j3-hydroxyesters (107), eight aminoesters (108), primary a-deuterioalcohols (109), and secondary carbinols (110). Even in a closely related series, exceptions have been found (110) in search of a predictable pattern. A study of nonequivalence in methyl alkyl sulfoxides with CLSR 54c (48) revealed a diminution of nonequivalence on increasing alkyl bulk with an inversion of sense between n-propyl and isopropyl. Changes in nonequivalence sense in several cases with different CSA-solute ratios were also observed. Presently, these CLSR configurational correlations remain totally empirical. 

Chiral sulfinates are important intermediates that are widely applied in the synthesis of other classes of chiral organosulfur compounds and in their configurational correlations. Optically active sulfinates were first prepared in 1925 by Phillips (100) in two ways. The first consisted in the transesterification of racemic alkyl p-toluenesulfin-ates with chiral alcohols such as (-)-menthol and (-)-2-octanol yielding a mixture of two optically active sulfinates as shown in eq. [26]. The... 

Configuration correlation diagram for the reaction C2H2 + C —> C3H2. 

Figure 3. Configurational correlation model for Mosher s MTPA derivatives (Figure adapted from15cd).

Figure 5. Configurational correlation model as proposed by Mosher and the modified Kakisawa view of L3 and L2. 5S minu5 5ft Hz (500 MHz)...

Figure 10 Free-ion term—strong-field configuration correlation diagrams for octahedral and tetrahedral stereochemistries (a) tfi and

As with 141, the ( + )- and (-)-benz[a]anthracene 8,9-oxides are prepared by the same sequence in optically pure form. The configuration of (—)-benz[a]anthracene 8,9-oxide (148) is unequivocally assigned as SS,9R by configurational correlation with the tetrahydrobenz[o]anthracene 149, whose absolute configuration is determined by X-ray crystallography.72... 

A value of one for S then implies that the ground configurations correlate and that the reaction is allowed, while a value of zero implies that the initial configuration correlates with some excited configuration of the product, so that the reaction is forbidden. 

It was in the famous carbohydrate group at Ohio State University that Lemieux became involved in the structural elucidation of streptomycin. He also became fascinated by the configurational correlation of sugars and amino acids, and realized that he could address this unresolved question by... 

---