109686-86-4

Upstream product

• 833-81-8 (E)-1,2-diphenylpropene 

Downstream Products

• 29835-15-2 2-methoxy-1,2-diphenylpropane 

Relevant academic research and scientific papers

GAS-SOLID REACTIONS IN ORGANIC SYNTHESIS

Various new branches in the field of preparative scale organic gas-solid reactions (additions, substitutions, eliminations, condensations) are elaborated following a historical review.Polar gases (HBr, HCl, HI, HSCH3) react at 1 bar and temperatures from 40 to -80 degC with gram quantities of crystalline N-vinylimides, -amides, -amines, and S-vinylthioethers usually in the Markovnikov orientation, but there is also an exception.The polar gases H2O and NH3 transform some of the crystalline addition products and H2O may be added catalytically to N-vinylphthalimide.All reactions run to high conversion rapidly and several of the highly sensitive products cannot be synthesized in soluton.Liquid compounds like N-vinylpyrrolidinone which polymerize in solution crystallize and add polar gases smoothly upon freezing.Polar gases are applied to crystalline chalcone, cinnamic acid, and stilbenes with variable success.Pd-doped crystals are hydrogenated.Contrary to literature reports chlorine and bromine add to crystalline stilbene non-stereospecifically and without significant substitution.The results are discussed with respect to X-ray structures and powder diffraction patterns.Educt and product crystals are not isotypical.Various solid state decompositions are uncovered and the synthetic value is stressed.

Organic Gas-Solid Reactions with Stilbenes, Chalcones, and Enamides

Crystalline stilbene (1) adds gaseous chlorine and bromine without intermediate melting.The stereoselectivity is similar to that observed in solutions.Triphenylethene (3) also yields the products 4 in gas-solid reactions with chlorine and bromine, but these products tend to loose HX from the crystal; their conversion products are described.Neither crystalline 1 nor 3, but (E)-1,2-diphenyl-1-propene (7) adds gaseous hydrogen bromide regiospecifically.The same is true for the crystalline chalcone 10, which adds hydrogen bromide and -chloride selectively to give 11 nonisotypically.Gaseous ammonia reconverts crystalline 11 into 10.The enamide 12 in its crystalline state adds the gases hydrogen bromide, -chloride, methanethiol and hydrogen, to give the products 13, but also 15 (addition and condensation) and 16 (double addition). 13f which is formed via hydrogenation of crystals is not isotypical with its precursor 12.The liquid 17 crstallizes on freezing and then easily adds the gases hydrogen bromide (> - 50 deg C) and hydrogen chloride (> - 80 deg C) in highly controlled reactions to give the reactive compounds 18.These are converted not only into oligomers but also into the derivatives 19, 20, 21, and 22.The advantages of the unusual reaction procedures are discussed.