Lignin models of the biphenyl type have been synthesized and crystal structures of two of them have been determined. The tetraacetate of 5,5′-bis(hydroxymethyl)-3,3′-dimethoxy-2,2′-biphenyldiol crystallizes in space group$$Pbar 1$$witha=11.319(2),b=12.232(6),c=9.242(3) Å, α=101.66(3)°, β=108.14(2)°, γ=79.08(2)° andZ=2.R=0.036 (2720 observed I>3σ(I) reflections). The acetate of 5,5′-di-tert-butyl-2′,3,3′-trimethoxy-2-biphenylol crystallizes in space group$$Pbar 1$$witha=11.972(2),b=21.621(3),c=9.834(1) Å, α=91.18(1)°, β=113.13(1)°. γ=98.42(1)°, andZ=4.R=0.050 (8129 observed I>3σ(I) reflections).1H NMR and13C NMR data for the above-mentioned compounds and a third model, the diacetate of 5,5′-bis(1-hydroxyethyl)-2,2′,3,3′-tetramethoxybiphenyl, are reported. Observed signal positions are compared with those calculated on the basis of crystal structure data. The possibilities to obtain structural information about biphenyl structures in ligni
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