1643958-21-7Relevant articles and documents
Selective Synthesis of C1-Symmetric BINOL-phosphates and P-chiral Phosphoramides Using Directed ortho-Lithiation
Volpe, Rohan,Law, Hanson Y.-L.,White, Jonathan M.,Flynn, Bernard L.
, p. 7055 - 7058 (2021)
Directed ortho-lithiation (DoL) has been developed as an effective method for the ortho-substitution of BINOL-phosphoric acid and BINOL-N-triflylphosphoramide (BINOL-P-acids). It can be employed in the rapid assembly of either mono- or disubstituted BINOL-P-acids, including unsymmetrical disubstitution through iterative DoL. Most significantly, DoL has proven to be highly effective in the diastereoselective desymmetrization of pseudo-C2-symmetric BINOL-N-triflylphosphoramide, affording a chiral P-group.
Catalytic Enantioselective Nazarov Cyclization
Jolit, Anais,Dickinson, Cody F.,Kitamura, Kei,Walleser, Patrick M.,Yap, Glenn P. A.,Tius, Marcus A.
, p. 6067 - 6076 (2017/11/14)
A detailed account of an asymmetric Nazarov cyclization that leads to α-hydroxycyclopentenones bearing either vicinal, all-carbon quaternary centers, or vicinal quaternary and tertiary centers is given. The all-aliphatic examples represent the greatest challenge, as the dienone starting materials are not activated toward cyclization by an aryl group. The rational design and optimization of the substrates in parallel with optimization of the chiral Br?nsted acid catalyst is also described, as well as a series of diastereoselective transformations of a fully substituted cyclopentenone product.