Results 81 to 90 of about 490 (165)
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Rhodium-Catalyzed Enantioselective Spiroannulation of 2-Alkenylphenols with Alkynes
Chinese Journal of Organic Chemistry, 2023Qing Gu
exaly +2 more sources
Prins-pinacol spiroannulations
Tetrahedron, 1997Abstract Lewis acid-promoted cyclizations of methylenecyclohexane siloxy acetals 14, 15 , and 21 afford spiro[4.5]decanones 22, 25 , and 29 in good yield. In all cases, exclusive pinacol rearrangement of C-1 of the original three-carbon acetal side chain is observed suggesting that pinacol rearrangement of the intermediate 9-decalyl cation ...
Keith P. Minor, Larry E. Overman
+4 more sources
Preservable Chirality in Carbocation-Mediated Spiroannulation
SynfactsDahui Zhao, Xinhang Chang
semanticscholar +2 more sources
The Journal of Organic Chemistry, 2023
A novel [4 + 1] and [5 + 1] dearomative spiroannulation has been developed by the use of commercial naphthols and phenols with dielectrophiles. Various spirocycles, including spiro[4.5] and spiro[5.5] have been constructed successfully by employing four-atom or five-atom dielectrophilic synthons.
Dongwei Zhao +4 more
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A novel [4 + 1] and [5 + 1] dearomative spiroannulation has been developed by the use of commercial naphthols and phenols with dielectrophiles. Various spirocycles, including spiro[4.5] and spiro[5.5] have been constructed successfully by employing four-atom or five-atom dielectrophilic synthons.
Dongwei Zhao +4 more
openaire +2 more sources
Dearomatizing [2+2+1] Spiroannulation of Indoles with Alkynes
Organic Letters, 2022A palladium-catalyzed dearomatizing [2+2+1] spiroannulation of indoles with two molecular internal alkynes is developed in the presence of Cu(OAc)2/O2 as the oxidant, in which a domino sequence including C-H activation of indole followed by consecutive Heck reactions is involved.
Xiao-Qing Han +4 more
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Spiroannulation by Alkylation and Reductive Cyclization of Nitriles
Angewandte Chemie International Edition, 2003AbstractFor Abstract see ChemInform Abstract in Full Text.
Scott D, Rychnovsky, Leo R, Takaoka
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Efficient and Convergent Stereocontrolled Spiroannulation of Ketones.
ChemInform, 2003AbstractFor Abstract see ChemInform Abstract in Full Text.
István E. Markó +4 more
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Regioselective Spiroannulations of α-Acetyl Lactones.
ChemInform, 2003AbstractMonocyclic spiroannulation precursors 3a−c were obtained by Michael reactions of α‐acetyl lactones 6a−c with methyl vinyl ketone (7). The selective formation of either regioisomer of both β‐oxo (5a−c) and δ‐oxo (4a−c) lactones from 3a−c was achieved by varying the reaction conditions. The δ‐oxo lactones 4a−c were obtained under basic (buffered)
Jens Christoffers +2 more
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A chemo- and regioselective Pd(0)-catalyzed three-component spiroannulation
Chemical Communications, 2021A novel Pd(0)-catalyzed three-component [2+2+1] dearomatizing reaction for the highly chemo- and regio-selective assembly of spirocarbocycles is described.
Jiaoyu Wu +4 more
openaire +2 more sources