Zobrazeno 1 - 10
of 17
pro vyhledávání: '"Johan Granander"'
Publikováno v:
The Journal of Organic Chemistry. 76:4794-4799
A new protocol for the catalytic asymmetric deprotonation of a phosphine borane using s-BuLi and substoichiometric quantities of chiral diamines is reported. The method involves three sequential additions of s-BuLi, and use of (-)-sparteine or the (+
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d98ef9fee45b49d820ab7f588b8279d5
https://doi.org/10.1021/jo200708e
https://doi.org/10.1021/jo200708e
Autor:
Jonathan J. Gammon, Johan Granander, Carsten Strohmann, Adrian C. Whitwood, Peter O'Brien, Brian Kelly, Viktoria H. Gessner, Barker Gregory
Publikováno v:
Journal of the American Chemical Society. 132:13922-13927
A systematic study of the asymmetric deprotonation of a dimethyl-substituted phosphine sulfide using organolithium bases in the presence of (-)-sparteine has been carried out. Use of nBuLi and (-)-sparteine in Et(2)O at -78 °C gave trapped adducts i
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d708b01814ca071c06d3b5fcaaed494b
https://doi.org/10.1021/ja1060966
https://doi.org/10.1021/ja1060966
Publikováno v:
Tetrahedron: Asymmetry. 19:1934-1940
Chiral diethyl (2R)-tetrahydropyrro-2-ylphosphonate is an effective catalyst for the Michael addition of nitroalkanes to α,β-unsaturated ketones. This study revealed that the hydrate salt of this α-aminophosphonate was found to be a better catalyt
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::1b67ad115b9b8053a3f9d4dfa9c7198f
https://doi.org/10.1016/j.tetasy.2008.07.007
https://doi.org/10.1016/j.tetasy.2008.07.007
Publikováno v:
Tetrahedron: Asymmetry. 17:2021-2027
Several asymmetric 1,2-additions of various organolithium reagents (methyllithium, n -butyllithium, phenyllithium, lithioacetonitrile, lithium n -propylacetylide, lithium phenylacetylide) to aldehydes are shown to result in decent to excellent enanti
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::50cfd0a8637a518b8858d64f8c4b4fe2
https://doi.org/10.1016/j.tetasy.2006.07.009
https://doi.org/10.1016/j.tetasy.2006.07.009
Publikováno v:
Journal of the American Chemical Society. 126:6798-6805
NMR spectroscopic studies have been performed on the mixed complexes formed by the lithium salt of acetonitrile (LiCH(2)CN) and the chiral lithium amides Li-(S)-N-(2-methoxybenzyl)-1-amino-1-phenyl-2-ethoxyethane (Li-1) and Li-(S)-N-isopropyl-2-amino
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d1bd1b0373837080a7a548fca654ca62
https://doi.org/10.1021/ja0388461
https://doi.org/10.1021/ja0388461
Publikováno v:
Tetrahedron: Asymmetry. 15:267-274
A series of chiral lithium amides with chelating sulfide groups has been investigated by NMR spectroscopy. These chiral lithium amides have previously been found to mediate higher enantioselectivity in the asymmetric addition of alkyllithium reagents
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::752222fc316625500f801f9e99a93b16
https://doi.org/10.1016/j.tetasy.2003.11.009
https://doi.org/10.1016/j.tetasy.2003.11.009
Publikováno v:
Tetrahedron. 58:4717-4725
Enantioselective butylation of benzaldehyde with n-butyllithium was mediated by a series of chiral lithium amide analogues to give 1-phenylpentanol in good to moderate enantioselectivities. In order to achieve high enantiomeric excess in the reaction
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::b6244b4d9cf7f4c4a4e01171cabeb52b
https://doi.org/10.1016/s0040-4020(02)00378-2
https://doi.org/10.1016/s0040-4020(02)00378-2
Publikováno v:
Tetrahedron: Asymmetry. 20:2432-2434
The attempted kinetic resolution of racemic secondary phosphine boranes [ t- BuPhP(BH 3 )H and t- BuMeP(BH 3 )H] by P–H deprotonation using 0.5 equiv of s -BuLi and (−)-sparteine was unsuccessful and generated racemic benzyl bromide-trapped adduc
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::22ea7e3d5d1b64eafb37708a5589bb68
https://doi.org/10.1016/j.tetasy.2009.10.026
https://doi.org/10.1016/j.tetasy.2009.10.026
Publikováno v:
ChemInform. 33
Enantioselective butylation of benzaldehyde with n-butyllithium was mediated by a series of chiral lithium amide analogues to give 1-phenylpentanol in good to moderate enantioselectivities. In order to achieve high enantiomeric excess in the reaction
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::2ef74593d1906eaa698a30b3aa8b4573
https://doi.org/10.1002/chin.200241038
https://doi.org/10.1002/chin.200241038
Publikováno v:
ChemInform. 40
Chiral diethyl (2R)-tetrahydropyrro-2-ylphosphonate is an effective catalyst for the Michael addition of nitroalkanes to α,β-unsaturated ketones. This study revealed that the hydrate salt of this α-aminophosphonate was found to be a better catalyt
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::8901484487bcb12e304c6aeb8a16acc2
https://doi.org/10.1002/chin.200911034
https://doi.org/10.1002/chin.200911034