140148-19-2Relevant academic research and scientific papers
Solid-phase synthesis of chiral N-acylethylenediamines and their use as ligands for the asymmetric addition of alkylzinc and alkenylzinc reagents to aldehydes
Sprout, Christopher M.,Richmond, Meaghan L.,Seto, Christopher T.
, p. 6666 - 6673 (2004)
A solid-phase procedure has been developed for the synthesis of chiral N-acylethylenediamine ligands. The ligands are obtained in good yield and purity, without the need for chromatography or other purification methods. Several new and previously reported ligands were prepared using this procedure. These compounds were examined as catalysts for the enantioselective addition of alkylzinc reagents to aldehydes. In all cases, the crude ligands from the solid-phase syntheses catalyzed the reactions with similar yields and stereoselectivities when compared to reactions using ligands that had been purified by standard methods. Preliminary studies were also performed with ligands 3a and 3f as catalysts for the addition of alkenylzinc reagents to aldehydes to give chiral allylic alcohols. Ligand 3f was found to catalyze this addition reaction in up to 76% ee.
PREPARATION OF ALLYLIC ALCOHOLS BY ALKENE TRANSFER FROM ZIRCONIUM TO ZINC
Wipf, Peter,Xu, Wenjing
, p. 5197 - 5200 (1994)
Transmetalation of alkenyl zirconocenes 2 to the corresponding organozinc compounds 3 occurs rapidly and at low temperature in the presence of stoichiometric amounts of commercially available dimethyl- or diethylzinc.Subsequent addition of aldehydes provides an in situ protocol for the conversion of alkynes 1 into allylic alcohols 5 in good to excellent yields.
Asymmetric epoxidation via phase-transfer catalysis: Direct conversion of allylic alcohols into α,β-epoxyketones
Lygo, Barry,To, Daniel C. M.
, p. 2360 - 2361 (2002)
Studies into the use of a chiral phase-transfer catalyst in conjunction with sodium hypochlorite to effect the enantio-selective formation of α,β-epoxyketones from allylic alcohols are described.
Dimethylzinc-promoted vinylation of nitrones with vinylboronic esters of pinacol: A new route to N-allylic hydroxylamines
Pandya, Shashi U.,Pinet, Sandra,Chavant, Pierre Y.,Vallee, Yannick
, p. 3621 - 3627 (2003)
Activation of vinylboronic esters of pinacol (alkenyl-4,4,5,5-tetramethyl-1,3,2-dioxaborolanes) with dimethylzinc allows nucleophilic addition of the vinyl group onto nitrones, producing N-allylic hydroxylamines in excellent yields. ( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003).
A chiral oxazoline for catalytic enantioselective Nozaki-Hiyama-Kishi allylation and vinylation of aldehydes
Chen, Chinpiao,Kumbhar, Sharad V.
, (2020/09/22)
Asymmetric allylation and vinylation of aldehydes with allyl halides and vinyl halides have been achieved using the chromium(II)-oxazoline catalyst. The catalyst promotes the highly efficient enantioselective Nozaki–Hiyama-Kishi (NHK) allylation of aldehydes using allyl bromide, producing the corresponding homoallylic alcohols in good yields (up to 84%) and a high level of enantioselectivity (up to 98% ee). Meanwhile, the NHK vinylation of aldehydes produce desired allylic alcohols in satisfactory yields (up to 88%) and a high level of enantioselectivity (up to 97% ee). We developed a reliable and milder protocol for preparing chiral homoallylic and allylic alcohols.
Size-Exclusion Borane-Catalyzed Domino 1,3-Allylic/Reductive Ireland–Claisen Rearrangements: Impact of the Electronic and Structural Parameters on the 1,3-Allylic Shift Aptitude
Fegyverneki, Dániel,Kolozsvári, Natália,Molnár, Dániel,Egyed, Orsolya,Holczbauer, Tamás,Soós, Tibor
supporting information, p. 2179 - 2183 (2019/01/04)
The reductive Ireland–Claisen rearrangement through borane-mediated hydrosilylation is reported. The method employs a borane catalyst with a special structural design and affords access to synthetically relevant products with high diastereoselectivity. Depending on electronic and structural parameters, the reaction can be coupled with a 1,3-allylic shift, thus the valence isomer of the Ireland–Claisen product is formed.
Accessing Both Retention and Inversion Pathways in Stereospecific, Nickel-Catalyzed Miyaura Borylations of Allylic Pivalates
Zhou, Qi,Srinivas, Harathi D.,Zhang, Songnan,Watson, Mary P.
supporting information, p. 11989 - 11995 (2016/10/07)
We have developed a stereospecific, nickel-catalyzed Miyaura borylation of allylic pivalates, which delivers highly enantioenriched α-stereogenic γ-aryl allylboronates with good yields and regioselectivities. Our complementary sets of conditions enable access to either enantiomer of allylboronate product from a single enantiomer of readily prepared allylic pivalate substrate. Excellent functional group tolerance, yields, regioselectivities, and stereochemical fidelities are observed. The stereochemical switch from stereoretention to stereoinversion largely depends upon solvent and can be explained by competitive pathways for the oxidative addition step. Our mechanistic investigations support a stereoretentive pathway stemming from a directed oxidative addition and a stereoinvertive pathway that is dominant when MeCN blocks coordination of the directing group by binding the nickel catalyst.
Tandem Benzylic Oxidation/Dihydroxylation of α-Vinyl- and α-Alkenylbenzyl Alcohols
Fernandes, Rodney A.,Kattanguru, Pullaiah
, p. 92 - 107 (2015/10/19)
A de novo tandem benzylic oxidative dihydroxylation of α-vinyl- and α-alkenylbenzyl alcohols has been developed to give α,β-dihydroxypropiophenones (=2,3-dihydroxy-1-phenylpropan-1-ones) and α,β-dihydroxyalkyl phenones. This method was shown to be substrate-selective and specific for the oxidation of benzylic alcohols.
(Z)-Selective enol triflation of α-alkoxyacetoaldehydes: Application to synthesis of (Z)-allylic alcohols via cross-coupling reaction and [1,2]-wittig rearrangement
Kurosawa, Fumiya,Nakano, Takeo,Soeta, Takahiro,Endo, Kohei,Ukaji, Yutaka
, p. 5696 - 5703 (2015/06/16)
The stereoselective transformation of α-alkoxyacetoaldehydes to the corresponding (Z)-vinyl triflates was achieved by treatment with phenyl triflimide and DBU. The stereochemistry was explained by the "syn-effect," which was attributed primarily to an σ → π interaction. The β-alkoxy vinyl triflates obtained were applied to the stereoselective synthesis of structurally diverse (Z)-allylic alcohols via transition metal-catalyzed cross-coupling reaction and [1,2]-Wittig rearrangement.
Copper(I)-mediated 1,2-metallate rearrangements of 1-metallated glycals
Jarowicki, Krzysztof,Kocieski, Philip,Komsta, Zofia,Wojtasiewicz, Anna
supporting information; experimental part, p. 946 - 952 (2012/05/04)
1,2-Metallate rearrangements involving reaction of 1-metallated glycals with organolithium reagents under copper(I) mediation give alkenylpolyol chains in 45-91% yield (19 examples). The reaction was applied to a formal synthesis of KRN7000 as well as a synthesis of a 5,6-ceramide derivative. Georg Thieme Verlag Stuttgart · New York.
