Synthesis of Chiral Tertiary Boronic Esters: Phosphonate-Directed Catalytic Asymmetric Hydroboration of Trisubstituted Alkenes
نویسندگان
چکیده
منابع مشابه
γ-Selective directed catalytic asymmetric hydroboration of 1,1-disubstituted alkenes.
Directed catalytic asymmetric hydroborations of 1,1-disubstituted alkenes afford γ-dioxaborato amides and esters in high enantiomeric purity (90-95% ee).
متن کاملCatalytic asymmetric synthesis of trisubstituted aziridines.
A method is described which provides for the direct asymmetric catalytic synthesis of trisubstituted aziridines from imines and diazo compounds. While unactivated imines were not reactive to α-diazo carbonyl compounds in which the diazo carbon was disubstituted, N-Boc imines react with both α-diazo esters and α-diazo-N-acyloxazolidinones to give trisubstituted aziridines with excellent diastere...
متن کاملProtodeboronation of tertiary boronic esters: asymmetric synthesis of tertiary alkyl stereogenic centers.
While tertiary boranes undergo efficient protodeboronation with carboxylic acids, tertiary boronic esters do not. Instead, we have discovered that CsF with 1.1 equiv of H2O (on tertiary diarylalkyl boronic esters) or TBAF·3H2O (on tertiary aryldialkyl boronic esters) effect highly efficient protodeboronation of tertiary boronic esters with essentially complete retention of configuration. Furthe...
متن کاملEfficient Synthesis of Chiral Trisubstituted 1,2-Allenyl Ketones by Catalytic Asymmetric Conjugate Addition of Malonic Esters to Enynes.
An N,N'-dioxide/scandium(III) complex catalyzed, highly efficient conjugate addition of malonic esters to enynes is described. A range of trisubstituted 1,2-allenyl ketones were obtained in high yields (up to 99 %) with good d.r. (up to 95/5) and excellent ee values (97 %-99 %). Moreover, the products could be easily transformed into chiral furan and 5-hydroxypyrazoline derivatives, both of whi...
متن کاملAte complexes of secondary boronic esters as chiral organometallic-type nucleophiles for asymmetric synthesis.
The addition of an aryllithium reagent to a secondary boronic ester leads to an intermediate boron-ate complex that behaves as a chiral nucleophile, reacting with a broad range of electrophiles with inversion of stereochemistry. Depending on the electrophile, the C-B bond can be converted into C-I, C-Br, C-Cl, C-N, C-O, and C-C, all with very high levels of stereocontrol. This discovery now add...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of the American Chemical Society
سال: 2017
ISSN: 0002-7863,1520-5126
DOI: 10.1021/jacs.7b02324