1: H2SO4 2: (thermal decarboxylation) View Scheme

(i) aq. H2SO4, (ii) (pyrolysis); Multistep reaction;

(thermal decarboxylation);

1: 6-bromoazulene With 1,1,1,2,2,2-hexabutyl-distannane; tetrakis(triphenylphosphine) palladium(0) in toluene 24 h; Heating; 2: 1-bromo-4-nitro-benzene With tri-tert-butyl phosphine; cesium fluoride; tris(dibenzylideneacetone)dipalladium (0) in 1,4-dioxane Stille cross-coupling; 2 h; Heating; Further stages.;

1: 6-bromoazulene With 1,1,1,2,2,2-hexabutyl-distannane; tetrakis(triphenylphosphine) palladium(0) in toluene 24 h; Heating; 2: 1-bromo-4-methoxy-benzene With tri-tert-butyl phosphine; cesium fluoride; tris(dibenzylideneacetone)dipalladium (0) in 1,4-dioxane Stille cross-coupling; 6 h; Heating; Further stages.;

1: 6-bromoazulene With 1,1,1,2,2,2-hexabutyl-distannane; tetrakis(triphenylphosphine) palladium(0) in toluene 24 h; Heating; 2: para-bromotoluene With tri-tert-butyl phosphine; cesium fluoride; tris(dibenzylideneacetone)dipalladium (0) in 1,4-dioxane Stille cross-coupling; 24 h; Heating; Further stages.;