1379681-83-0Relevant articles and documents
Efficient synthesis of 5-chalcogenyl-1,3-oxazin-2-ones by chalcogen-mediated yne-carbamate cyclisation: An experimental and theoretical study
Monlen, Alicia,Blay, Gonzalo,Domingo, Luis R.,Muoz, M. Carmen,Pedro, Jos R.
, p. 1020 - 1027 (2015)
A very efficient synthesis of 5-chalcogenyl-1,3-oxazin-2-ones has been accomplished by the chalcogen-mediated yne-carbamate cyclisation of chiral, non-racemic N-Cbz-protected propargylic amines using PhXY (X = Se, S, Te; Y = Br or Cl) as electrophile sources. The reactions gave good-toexcellent yields for a wide range of substrates. In all cases the reaction was totally regioselective, occurring by a 6-endo-dig process regardless of the nature of the reagent and of the substituents in the starting material. This methodology permits the formation of the 1,3-oxazin-2-one moiety as well as the simultaneous installation of a chalcogen functionality onto the heterocyclic ring. The experimental results have been rationalised by theoretical studies at the B3LYP/6-311G level of theory.
Enantioselective zinc/BINOL-catalysed alkynylation of aldimines generated in situ from α-amido sulfones
Blay, Gonzalo,Brines, Ana,Monleon, Alicia,Pedro, Jose R.
supporting information; experimental part, p. 2440 - 2444 (2012/03/26)
Chiral nonracemic N-Cbz-protected propargylic amines have been prepared by the addition of terminal alkynes to imines generated in situ from α-amido sulfones in the presence of diethylzinc and BINOL-type ligands as catalysts. The reactions give good yields and high enantioselectivities (ee values up to 95 %) for a good number of aromatic and heteroaromatic α-amido sulfones and alkynes. Copyright
