CI Pigment Yellow 74, α-(2-methoxy-4-nitrophenylhydrazono)-α-aceto-2'-methoxyacetanilide

Comparison of the structural motifs of acetoacetanilides and related azo pigments

“…6) follows the pattern set by the simple acetoacetanilides in that it is ortho substituted and thus has internal hydrogen bonding which gives a planar conformation. However, reviewing the work of previous authors (Paulus et al, 1983;Paulus, 1984;Gridunova et al, 1991;Paulus & Rieper, 1985;Whitaker, 1983aWhitaker, ,b, 1984aWhitaker, ,b, 1985aWhitaker, ,b,c, 1986Whitaker & Walker, 1987;Golinski, 1988) has shown us that for those anilides which show an intermolecular hydrogen bond, this is not necessarily retained in the simple monoazo pigments derived from these compounds and that in all cases, irrespective of the nature of any aryl ring substituents, the pigments show intramolecular hydrogen bonding similar to that found in (9). Furthermore, there appears to be no correlation between the aryl ring substituents and the dihedral angle between the ring plane and the plane of the amide.…”

“…To date, only the -naphthol (1) (Jarvis, 1961;Olivieri et al, 1989;Salmen et al, 1988;Whitaker, 1977Whitaker, , 1978bGrainger & McConnell, 1969;Guggenberger & Teufer, 1975;Diamantis et al, 1992;Alcock et al, 1968), naphthol AS (2) (Kobelt et al, 1972(Kobelt et al, , 1974Whitaker, 1978a) and acetoacetanilide (3) (Paulus et al, 1983;Paulus, 1984;Gridunova et al, 1991;Paulus & Rieper, 1985;Whitaker 1983aWhitaker ,b, 1984aWhitaker ,b, 1985aWhitaker ,b,c, 1986Whitaker & Walker, 1987;Golinski, 1988) classes of pigment have given crystal structures using standard laboratory techniques. The dif®culty in growing good quality crystals is further shown by the poor quality of some of these determinations (e.g.…”

CI Pigment Yellow 65, α-(4-methoxy-2-nitrophenylhydrazono)-α-aceto-2'-methoxyacetanilide

“…The first of these has been found in previously determined structures with similar values of the bond lengths. The second occurs in CI Pigment Yellow 74 (Whitaker & Walker, 1987), again with similar bond lengths. These hydrogen bonds will inhibit rotation about neighbouring bonds and tend to hold parts of the molecule planar.…”

“…This article is one of a series (Whitaker, 1983a(Whitaker, ,b, 1984a(Whitaker, ,b, 1985a(Whitaker, ,b, 1986Whitaker & Walker, 1985, 1987 concerned with the long-term aim of relating colour and crystal structure in acetoacetanilide pigments.…”

“…Yellow 74 (Whitaker & Walker, 1987). The pigment is commercially available and is used in oil media, especially for latex paints for exterior use.…”