Zobrazeno 1 - 10
of 16
pro vyhledávání: '"Katharina, Zielke"'
Publikováno v:
Asian journal of organic chemistry
The use of readily accessible ammonium ylides for (asymmetric) transformations, especially cyclization reactions, has received considerable attention over the past two decades. A variety of highly enantioselective protocols to facilitate annulation r
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f54f107362a17c98da3806dfd9974740
https://doi.org/10.1002/ajoc.201800091
https://doi.org/10.1002/ajoc.201800091
Autor:
Christina Gaunersdorfer, Michael Winter, Katharina Zielke, Mario Waser, Uwe Monkowius, Lukas Roiser
Publikováno v:
European Journal of Organic Chemistry. 2018:418-421
The use of carbonyl-stabilized ammonium- and sulfonium ylides allows for the synthesis of highly-functionalized trifluoroacetyl-substituted cyclopropanes. It turned out that the diastereoselectivities strongly depend on the nature of the chosen ylide
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::46f6c4c4e3ee4ca6c626797afa8cb3b6
https://doi.org/10.1002/ejoc.201701699
https://doi.org/10.1002/ejoc.201701699
Publikováno v:
Chemistry (Weinheim an der Bergstrasse, Germany)
The first highly asymmetric catalytic synthesis of densely functionalized dihydrobenzofurans is reported, which starts from ortho-hydroxy-containing para-quinone methides. The reaction relies on an unprecedented formal [4+1]-annulation of these quino
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=pmid________::d6ea270b68345e2a73826a89e949cd51
https://pubmed.ncbi.nlm.nih.gov/31020717
https://pubmed.ncbi.nlm.nih.gov/31020717
Autor:
David Díaz Díaz, Katharina Zielke, Marleen Häring, Judith Mayr, Mario Waser, Maximilian Tiffner
Publikováno v:
ChemistrySelect. 1:4030-4033
Ionene polymers were found to be versatile phase-transfer catalysts for a variety of different reactions like alpha-alkylation reactions or Michael addition reactions. Reasonably low catalyst loadings allowed us to obtain the target products under op
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::1355ced0a443d4d5dcb633ef4cd858b2
https://doi.org/10.1002/slct.201601140
https://doi.org/10.1002/slct.201601140
Publikováno v:
Synthesis. 50(20)
The formal (4+1) cyclization between in situ generated achiral carbonyl-stabilized ammonium ylides and vinylogous p-quinone methides can be carried out under operationally simple conditions, leading to two different double bond regioisomers depending
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e192f8e8918198bb817cf62fb9af23f2
https://pubmed.ncbi.nlm.nih.gov/30297974
https://pubmed.ncbi.nlm.nih.gov/30297974
Autor:
Katharina, Zielke, Mario, Waser
Publikováno v:
Organic Letters
The first (4 + 1)-annulation of o-quinone methides with α-branched allenoates as C1 synthons has been developed. This operationally simple protocol gives access to highly functionalized dihydrobenzofurans in an unprecedented fashion with excellent d
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=pmid________::45f21de5ce4bdda5da7f11d037a6f92f
https://pubmed.ncbi.nlm.nih.gov/29350040
https://pubmed.ncbi.nlm.nih.gov/29350040
Publikováno v:
Asian journal of organic chemistry
A straightforward phosphine-catalyzed formal [4+2] annulation between α-branched allenoates and arylidene azlactones has been developed to access highly functionalized spirocyclohexenes. This cyclization favors the γ-addition of the phosphine-activ
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e93154a336d75685aaabf5b19ec57d64
https://epub.jku.at/doi/10.1002/ajoc.201800275
https://epub.jku.at/doi/10.1002/ajoc.201800275
Enantioselective Catalytic [4+1]‐Cyclization of ortho‐Hydroxy‐para‐Quinone Methides with Allenoates.
Autor:
Zielke, Katharina1 (AUTHOR), Kováč, Ondřej2 (AUTHOR), Winter, Michael1 (AUTHOR), Pospíšil, Jiří2,3 (AUTHOR), Waser, Mario1 (AUTHOR) mario.waser@jku.at
Publikováno v:
Chemistry - A European Journal. 6/18/2019, Vol. 25 Issue 34, p8163-8168. 6p.
Autor:
Winter, Michael1, Gaunersdorfer, Christina1, Roiser, Lukas1, Zielke, Katharina1, Monkowius, Uwe2, Waser, Mario1 mario.waser@jku.at
Publikováno v:
European Journal of Organic Chemistry. 1/23/2018, Vol. 2018 Issue 3, p418-421. 4p.
Publikováno v:
Synthesis; 2018, Vol. 50 Issue 20, p4047-4054, 8p