6712-32-9Relevant academic research and scientific papers
Alcohol Dehydrogenases and N-Heterocyclic Carbene Gold(I) Catalysts: Design of a Chemoenzymatic Cascade towards Optically Active β,β-Disubstituted Allylic Alcohols
González-Granda, Sergio,Lavandera, Iván,Gotor-Fernández, Vicente
supporting information, p. 13945 - 13951 (2021/04/22)
The combination of gold(I) and enzyme catalysis is used in a two-step approach, including Meyer–Schuster rearrangement of a series of readily available propargylic alcohols followed by stereoselective bioreduction of the corresponding allylic ketone intermediates, to provide optically pure β,β-disubstituted allylic alcohols. This cascade involves a gold N-heterocyclic carbene and an enzyme, demonstrating the compatibility of both catalyst types in aqueous medium under mild reaction conditions. The combination of [1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene][bis(trifluoromethanesulfonyl)-imide]gold(I) (IPrAuNTf2) and a selective alcohol dehydrogenase (ADH-A from Rhodococcus ruber, KRED-P1-A12 or KRED-P3-G09) led to the synthesis of a series of optically active (E)-4-arylpent-3-en-2-ols in good yields (65–86 %). The approach was also extended to various 2-hetarylpent-3-yn-2-ol, hexynol, and butynol derivatives. The use of alcohol dehydrogenases of opposite selectivity led to the production of both allyl alcohol enantiomers (93->99 % ee) for a broad panel of substrates.
A Domino Strategy for the Synthesis of 2H-Pyrans from Propargyl Vinyl Ethers
Tejedor, David,Delgado-Hernández, Samuel,Diana-Rivero, Raquel,Díaz-Díaz, Abián,García-Tellado, Fernando
, p. 1784 - 1790 (2019/02/19)
Stable monocyclic 2H-pyrans are synthesized from readily available tertiary propargyl vinyl ethers via a metal-free all-pericyclic domino manifold involving a sequential propargyl Claisen rearrangement/[1,3]H-shift/oxa-6π electrocyclization set of reactions. The wide scope of this protocol is exemplified by the synthesis of 21 different 2H-pyrans incorporating a varied substitution pattern at the ring.
Gold-catalyzed isomerization of unactivated allenes into 1,3-dienes under ambient conditions
Ting, Chun-Ming,Hsu, Yi-Ling,Liu, Rai-Shung
supporting information; experimental part, p. 6577 - 6579 (2012/07/31)
We have developed a gold-catalyzed isomerization of unactivated allenes into 1,3-dienes with nitrosobenzene as an additive. This reaction proceeded almost exclusively at room temperature for highly substituted allenes. The utility of this reaction is manifested by the development of one-pot [4+2]-cycloaddition of allenes and reactive alkenes.
Using nazarov electrocyclization to stage chemoselective [1,2]-migrations: Stereoselective synthesis of functionalized cyclopentenones
Lebuf, David,Huang, Jie,Gandon, Vincent,Frontier, Alison J.
supporting information; experimental part, p. 10981 - 10985 (2011/12/16)
Highly functionalized cyclopentenones have been prepared stereospecifically through a chemoselective copper(II)-mediated Nazarov/Wagner-Meerwein rearrangement sequence. After the initial 4π electrocyclization, this reaction involves two sequential [1,2]-m
One-pot synthesis of optically active allyl esters via lipase-vanadium combo catalysis
Akai, Shuji,Hanada, Ryosuke,Fujiwara, Noboru,Kita, Yasuyuki,Egi, Masahiro
supporting information; experimental part, p. 4900 - 4903 (2011/01/12)
The combination of vanadium-oxo compounds (3 or 4) with a lipase produced the regio- and enantioconvergent transformation of racemic allyl alcohols (1 or 2) into optically active allyl esters. In this system, the vanadium compounds catalyzed the continuous racemization of the alcohols along with the transposition of the hydroxyl group, while the lipase effected the chemo- and enantioselective esterification to achieve the dynamic kinetic resolution.
Convenient generation of 1-propynyllithium. One-pot synthesis of acetylenic carbinols from 1,2-dibromopropane and aldehydes and ketones
Gribble,Joyner,Switzer
, p. 2997 - 3002 (2007/10/02)
Treatment of 1,2-dibromopropane (1) with 3 equiv of lithium diisopropylamide (-60° to 0°C, THF) generates 1-propynyllithium (2), which with aldehydes or ketones affords acetylenic carbinols 3 in 82-96% yields.
