827-69-0Relevant academic research and scientific papers
Lithium(1+)-catalyzed nazarov-type cyclization of 1-arylbuta-2,3-dien-1- ols: Synthesis of benzofulvene derivatives
Sai, Masahiro,Matsubara, Seijiro
, p. 2067 - 2071 (2014)
Lithium hexafluorophosphate proved to be an effective catalyst for a Nazarov-type cyclization of 1-arylbuta-2,3-dien-1-ols to afford benzofulvenes, valuable as building blocks for functional materials and bioactive compounds. Georg Thieme Verlag Stuttgart New York.
Highly Enantioselective Iridium-Catalyzed Hydrogenation of Conjugated Trisubstituted Enones
Peters, Bram B. C.,Jongcharoenkamol, Jira,Krajangsri, Suppachai,Andersson, Pher G.
supporting information, p. 242 - 246 (2021/01/13)
Asymmetric hydrogenation of conjugated enones is one of the most efficient and straightforward methods to prepare optically active ketones. In this study, chiral bidentate Ir-N,P complexes were utilized to access these scaffolds for ketones bearing the stereogenic center at both the α- and β-positions. Excellent enantiomeric excesses, of up to 99%, were obtained, accompanied with good to high isolated yields. Challenging dialkyl substituted substrates, which are difficult to hydrogenate with satisfactory chiral induction, were hydrogenated in a highly enantioselective fashion.
Cobalt-Catalyzed Asymmetric 1,4-Hydroboration of Enones with HBpin
Ren, Xiang,Lu, Zhan
supporting information, p. 8370 - 8374 (2021/11/01)
Herein, a series of new 8-OIQ cobalt complexes were synthesized and used for cobalt-catalyzed chemo- and enantioselective 1,4-hydroboration of enones with HBpin to access chiral β,β-disubstituted ketones with good to excellent chemo- and enantioselectivties. This protocol is operationally simple and shows a broad substrate scope.
Lewis Acid Catalyzed Ring-Opening Reaction of Cyclobutanones towards Conjugated Enones
Gao, Jiqiang,Guo, Ziteng,Li, Zhongjuan,Liu, Chunhui,Liu, Yu,Qiu, Tingtian,Zhang, Min,Zhao, Jinbo
, p. 6111 - 6114 (2021/12/16)
An unprecedented Fe-catalyzed ring-opening reaction of simple cyclobutanones is developed, which provides access to conjugated enones with good functional group tolerance in high yields under mild conditions. The product derivatization and gram-scale expe
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
, 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.
Catalytic Asymmetric Transfer Hydrogenation of trans-Chalcone Derivatives Using BINOL-derived Boro-phosphates
Na, Fei,Lopez, Susana S.,Beauseigneur, Alice,Hernandez, Lucas W.,Sun, Zhuoxin,Antilla, Jon C.
supporting information, p. 5953 - 5957 (2020/08/12)
Chiral phosphoric-acid-catalyzed asymmetric reductions of trans-chalcones have been investigated in this work. A BINOL-derived boro-phosphate-catalyzed asymmetric transfer hydrogenation of the carbon-carbon double bond of trans-chalcone derivatives employing borane as a hydride source was realized. This methodology provides a convenient procedure to access chiral dihydrochalone derivatives in high yields and with high enantioselectivities under mild conditions.
Capturing the Monomeric (L)CuH in NHC-Capped Cyclodextrin: Cavity-Controlled Chemoselective Hydrosilylation of α,β-Unsaturated Ketones
Bistri-Aslanoff, Olivia,Derat, Etienne,Leloux, Sébastien,Leyssens, Tom,Ménand, Micka?l,Meijide Suárez, Jorge,Riant, Olivier,Roland, Sylvain,Sollogoub, Matthieu,Xu, Guangcan,Zhang, Pinglu,Zhang, Yongmin
supporting information, p. 7591 - 7597 (2020/03/23)
The encapsulation of copper inside a cyclodextrin capped with an N-heterocyclic carbene (ICyD) allowed both to catch the elusive monomeric (L)CuH and a cavity-controlled chemoselective copper-catalyzed hydrosilylation of α,β-unsaturated ketones. Remarkably, (α-ICyD)CuCl promoted the 1,2-addition exclusively, while (β-ICyD)CuCl produced the fully reduced product. The chemoselectivity is controlled by the size of the cavity and weak interactions between the substrate and internal C?H bonds of the cyclodextrin.
Copper(II)-Catalyzed Tandem Decarboxylative Michael/Aldol Reactions Leading to the Formation of Functionalized Cyclohexenones
Lee, Jeonghyo,Wang, Sibin,Callahan, Miranda,Nagorny, Pavel
, p. 2067 - 2070 (2018/04/16)
This work describes the development of a new single-pot copper(II)-catalyzed decarboxylative Michael reaction between β-keto acids and enones, followed by in situ aldolization, which results in highly functionalized chiral and achiral cyclohexenones. The achiral version of this Robinson annulation features a hitherto unprecedented Michael reaction of β-keto acids with sterically hindered β,β′-substituted enones and provides access to all carbon quaternary stereocenter-containing cyclohexenones (11 examples, 43-83% yield). In addition, an asymmetric chiral bis(oxazoline) copper(II)-catalyzed single-pot Robinson annulation has been devised for preparing chiral cyclohexenones, including some products that contain vicinal stereocenters (5 examples, 65-85% yield, 84-94% ee). This latter protocol has been successfully applied to the enantioselective formation of the oxygenated 10-nor-steroid core from readily available starting materials.
Chiral 1,3,2-Diazaphospholenes as Catalytic Molecular Hydrides for Enantioselective Conjugate Reductions
Miaskiewicz, Solène,Reed, John H.,Donets, Pavel A.,Oliveira, Caio C.,Cramer, Nicolai
, p. 4039 - 4042 (2018/03/13)
Secondary 1,3,2-diazaphospholenes have a polarized P?H bond and are emerging as molecular hydrides. Herein, a class of chiral, conformationally restricted methoxy-1,3,2-diazaphospholene catalysts is reported. We demonstrate their catalytic potential in asymmetric 1,4-reductions of α,β-unsaturated carbonyl derivatives, including enones, acyl pyrroles, and amides, which proceeded in enantioselectivities of up to 95.5:4.5 e.r.
The synthesis of non-racemic β-alkyl-β-aryl-disubstituted allyl alcohols and their transformation into allylamines and amino acids bearing a quaternary stereocenter
Narczyk, Aleksandra,Pieczykolan, Micha?,Stecko, Sebastian
, p. 3921 - 3946 (2018/06/08)
A synthesis of non-racemic β-alkyl-β-aryl allyl alcohols and their transformation into allylamines bearing a quaternary stereogenic center is reported. The allyl alcohols were prepared either by Cu-catalyzed enantioselective reduction of enones or by sequ
