NMR coupling constants for

Table 3.23 NMR coupling constants for platinum phosphine complexes [155]...

In general there is a good correlation between bond distances in fused aromatic compounds and bond orders. Another experimental quantity that correlates well with the bond order of a given bond in an aromatic system is the nmr coupling constant for coupling between the hydrogens on the two carbons of the bond.74... 

Perlin effect smaller one-bond NMR coupling constants for the longer C-H bonds... 

H-NMR coupling constants. For such types of octahydronaphthalenes the values of J4a,8a usually less then 4 Hz in the cw-fused isomer and 11 Hz for the trans-fustd ones. For 49 and 50 14 is 7-8 Hz. Because of the presence of dioxolane rings the cyclohexane ring presumably adopts a distorted boat conformation. 

Reduction of (+)-dihydroquercetin with enzymes from cell suspension give the 2/ ,3S,4S-(2,3-/m 5-3,4-c/5)-flavan-3,4-diol (339, 342). H-NMR coupling constants for the tetra-O-methyl ether and the tetra-O-methyl ether diacetate derivatives as well as molecular mechanical studies indicate that these compounds exist exclusively in half-chair -conformations. The 2,3-cis flavan-3,4-diol methyl ethers also occur in solution predominantly in half-chair -conformations (304). 

Table 3.24 NMR coupling constants for platinum amine complexes [156J...

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