Numbering hydro positions

In the presence of Co2(CO)8, selectivity seems to depend on the number and relative position of the double bond substituents as well as on the reaction temperature. As is usually the case with Co2(CO)8, hydro-formylation leads mainly to the least branched aldehydes when the carbon a to the ring bears two substituents. However, when this carbon is monosubstituted, the ring effect becomes more important and CO insertion occurs on the benzylic position. 

When the two conditions of paragraph (a) are not fulfilled, positions in the skeleton of the corresponding hydrocarbon that are occupied by hetero atoms are denoted by a prefixes, and the parent heterocyclic compound is considered to be that which contains the maximum number of conjugated or isolated double bonds, but the corresponding hydrocarbon is named in the form in which it contains the maximum number of non-cumulative double bonds. Hydrogen additional to that present in the parent heterocyclic compound is named by hydro prefixes and/or as H in front of the a terms. 

Analysis of the TBPA-Ti complex (39,40) indicates that the binding site for the hormone is located deep inside the channel. The hormone makes extensive interactions with the protein side chains that project into the channel. The 4 -hydroxyl of Ti interacts with a patch of hydroxy-amino acids of the protein while each of the iodines makes contact with a number of hydro-phobic protein residues. The T amino acid side chain functional groups are in appropriate positions to interact with glutamic acid and lysine residues. Thus, this channel provides a favorable environment for each of the characteristic substituents of the thyroid hormone (40). However, because of the Ti orientation disorder in the protein complex, this structural model is not a sensitive measure of the observed correlations between diphenyl ether conformations and binding affinity data. 

The structural modification of the BINOL ligand system also plays an important role concerning stereoselection in the asymmetric Henry reaction. Improved enantioselectivites were obtained using a number of (.Rj-BINOL derivatives in which the 6,6 -positions were substituted [ 14]. Their utility as asymmetric catalysts was assessed with enantioselectivities up to 88% ee accompanied by chemical yields up to 85% in the nitroaldol reaction of nitromethane with hydro cinnamaldehyde 1. Whereas the substitution at the 6,6 -position of BINOL proved to be effective in obtaining superior asymmetric catalysts, the use of complexes derived from 3,3 -disubstituted BINOL derivatives [15,16] gave racemic 4 and BIPOL derived catalyst [17] gave 4 in only 39% ee. 

The applications of solid-state C-NMR spectra for the study of polymorphs and solvates can go beyond evaluations of resonance band positions and make use of additional spectral characteristics. For instance, studies of relaxation times of furosemide polymorphs were used to show the presence of more molecular mobility and disorder in Form II, while the structure of Form I was judged to be more rigid and uniformly ordered [158]. The analysis of the solid-state C-NMR spectra of (li ,3 j-3-/ -thioanisoyl)-l,2,2-trimethylcyclopentanecarboxylic acid was facilitated by the 7-modulated spin-echo technique, which was used to deduce the number of protons bound to each carbon atom [159]. Differences in the dipolar dephasing behavior between the two polymorphs of ( )- ra 5-3,4-dichloro-A/-methyl-7V-[ 1,2,3,4-tetrahydro-5-methoxy-2-(pyrrolidin-1 -yl)]naphth-1 -yl-benzeneacetamide were noted and ascribed to motional modulation of the carbon-hydro-... 

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