Zobrazeno 1 - 10
of 27
pro vyhledávání: '"Stephan Stanchev"'
Publikováno v:
Phosphorus, Sulfur, and Silicon and the Related Elements. 104:123-133
The addition of α-metallated sulfonamides to cyclic ketones has been studied. Under kinetic control the axial attack of the lithium and the cerium reagents to 4-tert-butylcyclohexanone is preferred, whereas the stereochemical result is inverse when
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9c068674b94d95edc54a5573026c35be
https://doi.org/10.1080/10426509508042584
https://doi.org/10.1080/10426509508042584
Publikováno v:
Tetrahedron: Asymmetry. 6:183-198
Synthesis and assignment of the absolute configuration of different types of compounds bearing the diarylmethane moiety is presented. The absolute configuration was determined using chemical correlation and CD approaches based on the sign of the 0-0
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9daa41a3292b9b2190c57f1bf0a13cd2
https://doi.org/10.1016/0957-4166(94)00374-k
https://doi.org/10.1016/0957-4166(94)00374-k
Publikováno v:
Tetrahedron: Asymmetry. 4:173-176
Michael addition of methyl vinyl ketone 2 to 2-nitrocycloalkanones 1 catalyzed by the Cinchona alkaloid cinchonine 3 affords adducts in high chemical yields in up to 60% enantiomeric excess. The configuration of the products depends on the ring size.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::65915b3dd50bc1b478033868b72f470c
https://doi.org/10.1016/s0957-4166(00)82330-7
https://doi.org/10.1016/s0957-4166(00)82330-7
Publikováno v:
ChemInform. 23
The reaction of racemic 2-phenylpropanal with methyl- and n-butyllithium was studied in detail. Factors such as temperature, solvent, rate of addition, presence of salts, scale-up and source of reagents were carefully examined. Cram-selectivities of
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::97e50f88322d56e917c44d4de703552e
https://doi.org/10.1002/chin.199249057
https://doi.org/10.1002/chin.199249057
Publikováno v:
ChemInform. 22
A short and efficient synthesis of the title compound based on racemate resolution is described.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::6f93f66e66752bd078bec8e1db6b09d4
https://doi.org/10.1002/chin.199109184
https://doi.org/10.1002/chin.199109184
Publikováno v:
ChemInform. 22
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::c0f938e832b2f5f89df1dc9b0dd91520
https://doi.org/10.1002/chin.199137130
https://doi.org/10.1002/chin.199137130
Publikováno v:
ChemInform. 23
The addition of metallated N,N-dialkyl-sulfonamides 1 to Mannich bases 2, leading to N,N-dialkylamides of 4-(N′,N′-dialkylamino)-2-hydroxy-2-phenylbutanesulfonic acids (4) is described.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::142d64e74f3c4a03b4fcd8d7454803a5
https://doi.org/10.1002/chin.199211128
https://doi.org/10.1002/chin.199211128
Publikováno v:
ChemInform. 24
Transmetalation of organolithium reagents RLi (R = CH3, n-Bu) with manganese pivalate produces reagents of the type RMnOC(O)tBu which react stereoselectively with substituted cyclohexanones to afford the axial alcohols preferentially. These reagents
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::303a6dcabc3af74551a7c43c92a07ed5
https://doi.org/10.1002/chin.199315084
https://doi.org/10.1002/chin.199315084
Publikováno v:
ChemInform. 24
Michael addition of methyl vinyl ketone 2 to 2-nitrocycloalkanones 1 catalyzed by the Cinchona alkaloid cinchonine 3 affords adducts in high chemical yields in up to 60% enantiomeric excess. The configuration of the products depends on the ring size.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::38012793e7922e191b39773809a8bea0
https://doi.org/10.1002/chin.199326044
https://doi.org/10.1002/chin.199326044
Autor:
Manfred T. Reetz, Stephan Stanchev
Publikováno v:
ChemInform. 24
Various organoiron(II) reagents undergo Grignard-type additions to substituted cyclohexanone derivatives, C–C bond formation occurring stereoselectively from the equatorial direction (97–100% selectivity).
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::030a63ee58334c0e1e41bb496a653c9c
https://doi.org/10.1002/chin.199324125
https://doi.org/10.1002/chin.199324125