85185-36-0Relevant academic research and scientific papers
Catalytic, enantioselective, intramolecular carbosulfenylation of olefins. preparative and stereochemical aspects
Denmark, Scott E.,Jaunet, Alex
supporting information, p. 140 - 171 (2014/01/17)
The first catalytic, enantioselective, intramolecular carbosulfenylation of isolated alkenes with aromatic nucleophiles is described. The combination of N-phenylsulfenylphthalimide, a chiral selenophosphoramide derived from BINAM, and ethanesulfonic acid as a cocatalytic Bronsted acid induced an efficient and selective cyclofunctionalization of various alkenes (aliphatic and aromatic) tethered to a 3,4-methylenedioxyphenyl ring. Under these conditions, 6-phenylthio-5,6,7,8-tetrahydronaphthalenes are formed diastereospecifically in good yields (50-92%) and high enantioselectivities (71:29-97:3 er). E-Alkenes reacted much more rapidly and with much higher selectivity than Z-alkenes, whereas electron-rich alkenes reacted more rapidly but with comparable selectivity to electron-neutral alkenes and electron-deficient alkenes. The Bronsted acid played a critical role in effecting reproducible enantioselectivity. A model for the origin of enantioselectivity and the dependence of rate and selectivity on alkene structure is proposed along with a rationale for the site selectivity in reactions with monoactivated arene nucleophiles.
Synthesis of the Aryltetralin Lignan Skeleton via the Prins Reaction
Snider, Barry B.,Jackson, Andrew C.
, p. 1471 - 1474 (2007/10/02)
Reaction of a 1,4-diaryl-1-butene (7) with paraformaldehyde and the appropriate alkylaluminum halide generates the cation 8, via addition of formaldehyde to the double bond, which cyclizes to give the aryltetralin 9.Reaction of 1,4-diphenyl-2-butene (6a) with paraformaldehyde and methylaluminum sesquichloride gives the ene adduct 5a, which reacts further, analogously to 7, to give 4a which possesses the aryltetralin lignan skeleton.
