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  • 1. Li, Jia-Qi
    et al.
    Liu, Jianguo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Krajangsri, Suppachai
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Chumnanvej, Napasawan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Singh, Thishana
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Andersson, Pher G.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Asymmetric Hydrogenation of Allylic Alcohols Using Ir-N,P-Complexes2016Inngår i: ACS Catalysis, ISSN 2155-5435, E-ISSN 2155-5435, Vol. 6, nr 12, s. 8342-8349Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, a series of gamma,gamma-disubstituted and beta,gamma-disubstituted allylic alcohols were prepared and successfully hydrogenated using suitable N,P-based Ir complexes. High yields and excellent enantioselectivities were obtained for most of the substrates studied. This investigation also revealed the effect of the acidity of the N,P-Ir-complexes on the acid sensitive allylic alcohols. DFT Delta pK(a) calculations were used to explain the effect of the N,P-ligand on the acidity of the corresponding Ir-complex. The selectivity model of the reaction was used to accurately predict the absolute configuration of the hydrogenated alcohols.

  • 2.
    Liu, Jianguo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Asymmetric hydrogenation of allylic alcoholsusing iridium catalysts2014Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The first part of this thesis is focussed on the enantioselective iridium catalyzeda symmetric hydrogenation of allylic alcohols. The study involved the preparation of a range of allylic alcohols. These allylic alcohols were then hydrogenated, using iridium catalysts that have been previously prepared, to produce chiral alcohols with high yields and excellent enantioselectivity. The selectivity model of the reaction was used to accurately predict the absolute configuration of the hydrogenated products.

    The second part of the thesis was directed on the application of iridium catalyzed asymmetric hydrogenation of allylic alcohols in the synthesis of a late-stage intermediate of Aliskiren. A total of three synthetic routes were evaluated. The best synthesis relies on asymmetric hydrogenation of an allylic ester and an allylic alcohol as key-steps. Full conversion and 94% ee for the allylic alcohol were achieved. The late-stage intermediate of Aliskiren was successfully synthesized in eight steps.

  • 3.
    Liu, Jianguo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Iridium Catalysed Asymmetric Hydrogenation of Olefins and Dynamic Kinetic Resolution in the Asymmetric Hydrogenation of Allylic Alcohols2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The work described in this thesis is focused on exploring the efficacy of iridium-catalysed asymmetric hydrogenation of precursors to chiral alcohols and chiral cyclohexanes. A range of allylic alcohols including γ,γ-dialkyl allylic alcohols and (Z)-allylic alcohols were prepared and evaluated in the asymmetric hydrogenation using iridium catalysts resulting in chiral alcohols in high yields and excellent enantioselectivity. This methodology was applied in the formal synthesis of Aliskiren, an efficient renin inhibitor drug, using the asymmetric hydrogenation of an allylic alcohol as a key-step. Another project concerned the dynamic kinetic resolution of racemic secondary allylic alcohols using Ir-N,P catalysts under hydrogenation conditions. A range of secondary allylic alcohols and protected alcohols were evaluated in the asymmetric hydrogenation via dynamic kinetic resolution using Ir-N,P catalysts. The corresponding chiral saturated alcohols were formed in good yield with excellent diastereoselectivites (up to 95/5) and enantioselectivities (>99% ee). The last part of this thesis is directed towards the development of highly regio- and enantioselective asymmetric hydrogenation of 1,4-cyclohexadienes and its application in the preparation of useful chiral cyclohexenone intermediates. Non-functionalised, functionalised and heterocycle-containing cyclohexadienes were evaluated. Good yield of regioselectively mono-hydrogenated silyl protected enol ethers were obtained in most cases with excellent enantioselectivity. 

  • 4.
    Liu, Jianguo
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Krajangsri, Suppachai
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Li, Jiaqi
    Andersson, Pher G.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Iridium-catalyzed Asymmetric Hydrogenation of Allylic Alcohols via Dynamic Kinetic ResolutionManuskript (preprint) (Annet vitenskapelig)
  • 5.
    Liu, Jianguo
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Krajangsri, Suppachai
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Singh, Thishana
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    De Seriis, Giulia
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Chumnanvej, Napasawan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Wu, Haibo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Andersson, Pher G.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Regioselective Iridium-Catalyzed Asymmetric Monohydrogenation of 1,4-Dienes2017Inngår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 139, nr 41, s. 14470-14475Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A highly efficient regio- and enantioselective monohydrogenation of 1,4-dienes has been realized using an iridium catalyst with a chiral N,P-ligand under mild conditions. The substrate scope was studied and included both unfunctionalized as well as functionalized substituents on the meta- or para-position. Substrates having substituents with functionalities such as silyl protected alcohols or ketals were monohydrogenated in high regioselectivity and high enantiomeric excess (up to 98% ee).

  • 6.
    Peters, Byron K.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Liu, Jianguo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Margarita, Cristiana
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Andersson, Pher G.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Formal Total Synthesis of Aliskiren2015Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 21, nr 19, s. 7292-7296Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The efficient and selective formal total synthesis of aliskiren is described. Aliskiren, a renin inhibitor drug, has received considerable attention, primarily because it is the first of the renin inhibitor drugs to be approved by the FDA. Herein, the formal synthesis of aliskiren by iridium-catalyzed asymmetric hydrogenation of two allylic alcohol fragments is reported. Screening a number of N,P-ligated iridium catalysts yielded two catalysts that gave the highest enantioselectivity in the hydrogenation, which gave the saturated alcohols in 97 and 93% ee. In only four steps after hydrogenation, the fragments were combined by using the Julia-Kocienski reaction to produce late-stage intermediate in an overall yield of 18%.

  • 7.
    Peters, Byron K.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Liu, Jianguo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Margarita, Cristiana
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Rabten, Wangchuk
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kerdphon, Sutthichat
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Orebom, Alexander
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Morsch, Thomas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Andersson, Pher G.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Enantio- and Regioselective Ir-Catalyzed Hydrogenation of Di- and Trisubstituted Cycloalkenes2016Inngår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 138, nr 36, s. 11930-11935Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A number of cyclic olefins Were prepared and evaluated for the asymmetric hydrogenation reaction using novel N,P-ligated iridium imidazote-based Catalysts (Crabtree type). The diversity of these cyclic olefins spanned those having little functionality to others bearing strongly coordinating substituents and heterocycles. Excellent enantioselectivities were observed both for substrates having little functionality (up to >99% ee) and for substrates possessing functional groups several carbons away from the olefin. Substrates having functionalities such as carboxyl groups, alcohols, or heterocycles in the vicinity of the C=C bond were hydrogenated in high enantiomeric excess (up to >99% ee). The hydrogenation was also found to be regioselective, and by controlling the reaction conditions, selective hydrogenation of one of two trisubstituted olefins can be achieved: Furthermore, trisubstituted olefins can be selectively hydrogenated in the presence of tetrasubstituted olefins.

  • 8.
    Peters, Byron K.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Liu, Jianguo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Margarita, Cristiana
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Rabten, Wangchuk
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kerdphon, Sutthichat
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Paptchikhine, Alexander
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Andersson, Pher
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Enantio- and Regioselective Hydrogenation of Minimally and Densely Decorated Unsaturated CarbocyclesManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Several cyclic prochiral olefins were successfully hydrogenated (>99 conv.,up to >99 % ee) using N,P-ligated iridium catalysts. Minimally functionalisedsubstrates (Class 1) were hydrogenated rapidly and in high ee, whichwas consistent with earlier reports. Substrates having functional groups(Class 2) and heterocycles (Class 3) attached to the unsaturated cycle, were43hydrogenated gradually over a period of time, however, high enantioselectivitywas still maintained (up to >99 % ee). This methodology is a highly practical,general and selective means of preparing chiral cyclohexanes.

  • 9.
    Xu, Quan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Liu, Jianguo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Rabten, Wangchuk
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Diomedi, Simone
    Singh, Thishana
    Andersson, Pher G.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Thiazole, Imidazole and Oxazoline Based N,P-Ligands for Palladium-Catalyzed Cycloisomerization of 1,6-Enynes2016Inngår i: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, nr 20, s. 3427-3433Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of N,P-ligands were prepared and evaluated in the asymmetric palladium-catalyzed cycloisomerization of allyl propargyl ether substrates. The reactivity and enantioselectivity of the reaction was shown to be highly dependent on the chiral skeleton of the ligand structures with ee's ranging from 22-99 %. The proton source had a significant impact on the enantioselectivity. The generation of palladium hydride from formic acid led to the highest ee. A selectivity model based on a proposed transition state was used to predict and explain the enantiomeric outcome of the reaction.

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