Silver(I)-Catalyzed Aminocyclization of 2,3-Butadienyl and 3,4-Pentadienyl Carbamates: An Efficient and Stereoselective Synthesis of 4-Vinyl-2-oxazolidinones and 4-Vinyltetrahydro-2H-1,3-oxazin-2-ones
Regioselective Propargylation of Aldehydes and Ketones by Electrochemical Reaction using Zinc and Aluminum Anodes
作者:Nobuhito Kurono、Kazuya Sugita、Masao Tokuda
DOI:10.1016/s0040-4020(99)01089-3
日期:2000.2
Electrochemical propargylation of aldehydes and ketones with unsubstituted or α-substituted propargylic bromides using platinum cathode and zinc anode proceeded efficiently under mild conditions to give the corresponding homopropargyl alcohols exclusively in high yields. Similar electrochemical propargylation with γ-substituted propargyl bromides gave the corresponding homoallenyl alcohols as major
C−C-Bond Formation by the Palladium-Catalyzed Cycloisomerization/Dimerization of Terminal Allenyl Ketones: Selectivity and Mechanistic Aspects
作者:A. Stephen K. Hashmi、Thorsten L. Ruppert、Thomas Knöfel、Jan W. Bats
DOI:10.1021/jo970837l
日期:1997.10.1
conditions, besides the normal functional group tolerance known for palladium-catalyzed reactions, an interesting selectivity was observed with functional groups that are known to react either in palladium-catalyzed reactions or reactions catalyzed by other transition-metals. Thus aryl halides, terminal alkynes, 1,6-enynes, and alpha-allenic alcohols were tolerated. In the latter example the selective reaction
Studies on the radical addition reaction of perfluoroalkyl iodides with 2,3-allenols and the Pd-catalyzed kinetic resolution via Sonogashira coupling reaction
作者:Zhichao Ma、Rong Zeng、Chunling Fu、Shengming Ma
DOI:10.1016/j.tet.2011.08.044
日期:2011.11
A radical addition reaction promoted by Na2S2O4 of perfluoroalkyliodides with 2,3-allenols affording E/Z mixtures of 3-iodo-4-perfluoroalkyl-substituted allylic alcohols has been studied. Kinetic resolution with Sonogashira coupling reaction was applied to afford the Z isomer of 3-iodo-4-perfluoroalkyl-substituted allylic alcohol (Z-3) and the E isomer of conjugated enynic diols (E-5) in 39–52% and
已经研究了由全氟烷基碘化物的Na 2 S 2 O 4与2,3-烯醇促进的自由基加成反应,得到3碘-4-全氟烷基取代的烯丙基醇的E / Z混合物。与Sonogashira偶联反应动力学拆分施加到得到Ž 3-碘-4-全氟烷基-取代的烯丙醇的异构体(ž - 3)和Ë缀合enynic二醇(异构体ë - 5)在39-52%和22分别为–40%的收益率。
A highly stereoselective preparation of <i>syn</i>-1,2-diols from secondary α-allenic alcohols via iodocyclization. Synthesis of (±)-<i>threo</i>-L-factor and (±)-disparlure
作者:Richard W. Friesen、André Giroux
DOI:10.1139/v94-236
日期:1994.8.1
The iodocyclization of the N-tosyl carbamates 5 of secondary α-allenic alcohols 4 is described. The reaction sequence involves the addition of iodine to the terminal olefin of the allene moiety of 5 resulting in the formation of an isomeric mixture of Z and E diiodides 6 and 7. This initial process is followed, in the same pot, by reaction of the diiodides with silver carbonate. Hydrolysis of the resulting
Synthesis and reactions of 1,2-disubstituted methylenecyclopropanes prepared via intramolecular cyclopropanation of allenic diazoacetates
作者:Mark Lautens、Christophe Meyer、Arjan van Oeveren
DOI:10.1016/s0040-4039(97)00765-x
日期:1997.6
Diazoacetates derived from α- or β- allenic alcohols, prepared using the glyoxylic acid chloride p-toluenesulfonylhydrazone method, undergo regioselective intramolecular cyclopropanation in the presence of a copper (II) catalyst in refluxing toluene, leading to synthetically useful di- or trisubstituted methylenecyclopropyl lactones. The diastereoselectivity of the process has been studied.