129063-99-6Relevant academic research and scientific papers
Chromium(II)-Mediated Stereodivergent Additions of Allylic Phosphates and Halides to Aldehydes
Nowotny, Stefan,Tucker, Charles E.,Jubert, Carole,Knochel, Paul
, p. 2762 - 2772 (1995)
The addition of γ-disubstituted allylchromium(III) reagents to aldehydes proceeds in a stereodivergent manner, in contrast to the case of γ-monosubstituted allylchromium(III) species.The method allows the preparation of a variety of homoallylic alcohols bearing a quaternary center of defined relative configuration in the α-position.The preparation of both stereomeric homoallylic alcohols 13 is possible by using either of the two (E)- or (Z)-allylic precursors.The reaction has been extended to a γ-monosubstituted β-(trimethylsilyl)allylic system.The intermediate allylic chromium(III) reagents can be conveniently prepared from the corresponding phosphates (or chlorides) in DMPU or THF in the presence of catalytic amounts of LiI.
Diastereo-, Enantio-, and anti-Selective Formation of Secondary Alcohol and Quaternary Carbon Stereocenters by Cu-Catalyzed Additions of B-Substituted Allyl Nucleophiles to Carbonyls
Wheatley, Emilie,Zanghi, Joseph M.,Meek, Simon J.
, p. 9269 - 9275 (2020)
A general method for the synthesis of secondary homoallylic alcohols containing α-quaternary carbon stereogenic centers in high diastereo- and enantioselectivity (up to >20:1 dr and >99:1 er) is disclosed. Transformations employ readily accessible aldehydes, allylic diboronates, and a chiral copper catalyst and proceed by γ-addition of in situ generated enantioenriched boron-stabilized allylic copper nucleophiles. The catalytic protocol is general for a wide variety of aldehydes as well as a variety of 1,1-allylic diboronic esters. Hammett studies disclose that diastereoselectivity of the reaction is correlated to the electronic nature of the aldehyde, with dr increasing as aldehydes become more electron poor.
A stereoselective synthesis of 3,3-disubstituted allylborane derivatives using haloboration reaction and their application for the diastereospecific synthesis of homoallylic alcohols having quaternary carbon
Sato,Yamamoto,Hara,Suzuki
, p. 7071 - 7074 (2007/10/02)
3,3-Disubstituted allylborane derivatives (1c) can be prepared stereoselectively from the haloboration adducts of 1-alkynes and they afford homoallylic alcohols having quaternary carbon (2c) diastereospecifically by the reaction with aldehydes.
Stereoselective Synthesis of Alcohols, XXXVI Stereoselective Generation of Homoallyl Alcohols Having Quarternary Stereogenic Centers
Hoffmann, Reinhard W.,Schlapbach, Achim
, p. 1243 - 1248 (2007/10/02)
E- and Z-γ,γ-disubstituted allylboronates 12 have been generated by the carbocupration of alkynes and subsequent homologation.These allylboronates add to aldehydes, forming the homoallyl alcohols 13 and 14 with 88-99percent simple diastereoselectivity.The
