6704-77-4Relevant articles and documents
Sulfur-ylide-mediated synthesis of functionalized and trisubstituted epoxides with high enantioselectivity; Application to the synthesis of CDP-840
Aggarwal, Varinder K.,Bae, Imhyuck,Lee, Hee-Yoon,Richardson, Jeffery,Williams, David T.
, p. 3274 - 3278 (2007/10/03)
Benzyl and substituted allyl sulfonium salts react with a broad range of simple and functionalized aldehydes and ketones to give epoxides with high diastereoselectivity and high enantioselectivity (see scheme). The process has been applied to a short synthesis of the phosphodiesterase-IV inhibitor CDP-840. R1, R2 = hydrogen, alkyl, alkenyl, alkynyl, aryl, or pyridyl.
Catalytic asymmetric synthesis of epoxides from aldehydes using sulfur ylides with in situ generation of diazocompounds
Aggarwal, Varinder K.,Alonso, Emma,Hynd, George,Lydon, Kevin M.,Palmer, Matthew J.,Porcelloni, Marina,Studley, John R.
, p. 1430 - 1433 (2007/10/03)
A practical, general, and convergent to epoxides with control of the relative and absolute stereochemistry has been achieved by generating the reactive intermediate (the diazo compound) in situ from tosylhydrazone salts (see scheme, PTC = phase-transfer catalyst, Ts = toluene-4-sulfonyl). High yields (58-82%), high d.r. (88:12-98:2), and high ee values (87-94%) have been obtained using a new class of stable chiral sulfides at low catalyst loading (5 mol%) and [Rh2(OAc)4] (0.5 mol%).
