4452-11-3

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• β-Iodo Ketones by Prevost Reaction of Vinyl Carbinols
• Treatment of α-ethenyl-α-phenylbenzenemethanol with iodine and silver acetate in either acetic acid or benzene gave 1,2-diphenyl-3-iodo-1-propanone (6) in 85percent yield.Ring enlargements involving similar rearrangements were observed with a number of cy
• Ciganek, Engelbert,Calabrese, J. C.

• p. 4439 - 4443

  (1995)
• Read Online

• Boron trifluoride mediated allylation of aromatic α-bromoketones by allyltributyltin
• Replacement of bromine atom of aromatic α-brormoketones by allyltributyltin in the presence of BF3 was described. The reaction proceeds with or without migration of the aryl group, depending on the structure of the α-bromoketone.
• Miyake, Hideyoshi,Hirai, Ryo,Nakajima, Yoshie,Sasaki, Mitsuru

• p. 164 - 165

  (2003)
• Read Online

• Specific alkylidene coupling of the labile diruthenium bridging methylene complex [(η-C5H5)2Ru2(μ-CH 2)(CO)2(MeCN)] with diazoalkanes (N2=CR2) giving alkenic products
• Reaction of the labile diruthenium bridging methylene complex [(η-C5H5)2Ru2(μ-CH 2)(μ-CO)(CO)(MeCN)] with diazoalkanes (N2=CR1R2) results in specific C-C coupling to g
• Akita, Munetaka,Hua, Ruimao,Knox, Selby A. R.,Moro-oka, Yoshihiko,Nakanishi, Sadahiro,Yates, Michael I.

• p. 51 - 52

  (1997)
• Read Online

• Chemoselective reduction of ?,￠-unsaturated carbonyl and carboxylic compounds by hydrogen iodide
• The selective reduction of ?,￠-unsaturated carbonyl compounds was achieved to produce saturated carbonyl compounds with aqueous HI solution. The introduction of an aryl group at an ? or ￠ position efficiently facilitated the reduction with good yield. The reaction was applicable to compounds bearing carboxylic acids and halogen atoms. Through the investigation of the reaction mechanism, it was found that Michael-type addition of iodide occurred to produce ￠-iodo compounds followed by the reduction of C-I bond via anionic and radical paths.
• Matsumoto, Shoji,Marumoto, Hayato,Akazome, Motohiro,Otani, Yasuhiko,Kaiho, Tatsuo

• p. 590 - 599

  (2021/03/29)
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• Asymmetric Catalytic Epoxidation of Terminal Enones for the Synthesis of Triazole Antifungal Agents
• An enantioselective epoxidation of α-substituted vinyl ketones was realized to construct the key epoxide intermediates for the synthesis of various triazole antifungal agents. The reaction proceeded efficiently in high yields with good enantioselectivities by employing a chiral N,N′-dioxide/ScIII complex as the chiral catalyst and 35% aq. H2O2 as the oxidant. It enabled the facile transformation for optically active isavuconazole, efinaconazole, and other potential antifungal agents.
• Feng, Xiaoming,He, Qianwen,Liu, Xiaohua,Zhang, Dong,Zhang, Fengcai
• supporting information

  p. 6961 - 6966

  (2021/09/11)
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• Iron-Catalyzed Enantioselective Radical Carboazidation and Diazidation of α,β-Unsaturated Carbonyl Compounds
• Azidation of alkenes is an efficient protocol to synthesize organic azides which are important structural motifs in organic synthesis. Enantioselective radical azidation, as a useful strategy to install a C-N3 bond, remains challenging due to the inherently instability and unique structure of radicals. Here, we disclose an efficient enantioselective radical carboazidation and diazidation of α,β-unsaturated ketones and amides catalyzed by chiral N,N′-dioxide/Fe(OTf)2 complexes. An array of substituted alkenes was transformed to the corresponding α-azido carbonyl derivatives in good to excellent enantioselectivities, benefiting the preparation of chiral α-amino ketones, vicinal amino alcohols, and vicinal diamines. Control experiments and mechanistic studies proved the radical pathway in the reaction process. The DFT calculations showed that the azido transferred to the radical intermediate via an intramolecular five-membered transition state with the internal nitrogen of the Fe-N3 species.
• Dong, Shunxi,Feng, Xiaoming,He, Jun,Liu, Wen,Liu, Xiaohua,Pu, Maoping,Wu, Yun-Dong,Zhang, Tinghui
• supporting information

  p. 11856 - 11863

  (2021/08/16)
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• Formal Enone α-Arylation via I(III)-Mediated Aryl Migration/Elimination
• A formal enone α-arylation is described. This metal-free transformation relies on the I(III)-mediated skeletal reorganization of silyl enol ethers and features mild conditions, good yields, and high stereoselectivities for β-substituted enones.
• Martins, Bruna S.,Kaiser, Daniel,Bauer, Adriano,Tiefenbrunner, Irmgard,Maulide, Nuno

• p. 2094 - 2098

  (2021/04/05)
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• Cu/Pd-catalyzed borocarbonylative trifunctionalization of alkynes and allenes: synthesis of β-geminal-diboryl ketones
• Functionalized bisboryl compounds have recently emerged as a new class of synthetically useful building blocks in organic synthesis. Herein, we report an efficient strategy to synthesize β-geminal-diboryl ketones enabled by a Cu/Pd-catalyzed borocarbonylative trifunctionalization of readily available alkynes and allenes. This reaction promises to be a useful method for the synthesis of functionalized β-geminal-diboryl ketones with broad functional group tolerance. Mechanistic studies suggest that the reaction proceeds through borocarbonylation/hydroboration cascade of both alkynes and allenes. [Figure not available: see fulltext.]
• Yuan, Yang,Wu, Fu-Peng,Spannenberg, Anke,Wu, Xiao-Feng

• p. 2142 - 2153

  (2021/09/06)
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• Bromomethyl Silicate: A Robust Methylene Transfer Reagent for Radical-Polar Crossover Cyclopropanation of Alkenes
• A general protocol for visible-light-induced cyclopropanation of alkenes was developed with bromomethyl silicate as a methylene transfer reagent, offering a robust tool for accessing highly valuable cyclopropanes. In addition to α-aryl or methyl-substituted Michael acceptors and styrene derivatives, the unactivated 1,1-dialkyl ethylenes were also shown to be viable substrates. Apart from realizing the cyclopropanation of terminal alkenes, the methyl transfer reaction has been further demonstrated to be amenable to the internal olefins. The photocatalytic cyclopropanation of 1,3-bis(1-arylethenyl)benzenes was also achieved, giving polycyclopropane derivatives in excellent yields. With late-stage cyclopropanation as the key strategy, the synthetic utility of this transformation was also demonstrated by the total synthesis of LG100268.
• Luo, Wenping,Fang, Yewen,Zhang, Li,Xu, Tianhang,Liu, Yongjun,Li, Yan,Jin, Xiaoping,Bao, Jiakan,Wu, Xiaodong,Zhang, Zongyong
• supporting information

  p. 1778 - 1781

  (2020/03/11)
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• Br?nsted Base-Catalyzed Transformation of α,β-Epoxyketones Utilizing [1,2]-Phospha-Brook Rearrangement for the Synthesis of Allylic Alcohols Having a Tetrasubstituted Alkene Moiety
• A stereoselective transformation of α,β-epoxyketones into alkenylphosphates having a hydroxymethyl group on the β-carbon was established by utilizing the [1,2]-phospha-Brook rearrangement under Br?nsted base catalysis. The reaction involves the catalytic generation of an α-oxygenated carbanion located at the α-position of an epoxide moiety through the [1,2]-phospha-Brook rearrangement and the following epoxide opening. Further transformation of the alkenylphosphates by the palladium-catalyzed cross-coupling reaction with Grignard reagents provided allylic alcohols having a stereodefined all-carbon tetrasubstituted alkene moiety.
• Kondoh, Azusa,Tasato, Naoko,Aoki, Takuma,Terada, Masahiro
• supporting information

  p. 5170 - 5175

  (2020/07/04)
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• Intermolecular scandium triflate-promoted nitrene-transfer [5 + 1] cycloadditions of vinylcyclopropanes
• Sc(OTf)3-promoted [5 + 1] cycloaddition of vinylcyclopropanes with PhINTs is reported, enabling the regioselective preparation of a range of 1,2,3,6-tetrahydropyridine scaffolds under mild conditions. This represents the second example of a [5
• Laudenschlager, Julie E.,Combee, Logan A.,Hilinski, Michael K.
• supporting information

  p. 9413 - 9417

  (2019/11/14)
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• Stereodivergent Access to Enantioenriched Epoxy Alcohols with Three Stereogenic Centers via Ruthenium-Catalyzed Transfer Hydrogenation
• The resolution technique of stereodivergent reaction on racemic mixtures (stereodivergent RRM) was employed for the first time in ruthenium complex catalyzed transfer hydrogenation of racemic epoxy ketones, providing a new and very simple method that allows access to enantioenriched epoxy alcohols with three stereogenic centers in a one-step fashion. The protocol features simple reaction conditions, practical operation, ability to scale up, and broad group tolerance.
• Zhao, Zhifei,Bagdi, Prasanta Ray,Yang, Shuang,Liu, Jinggong,Xu, Weici,Fang, Xinqiang
• supporting information

  p. 5491 - 5494

  (2019/08/01)
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• Alkylation of Indoles with α,β-Unsaturated Ketones using Alumina in Hexanes
• We evaluated the influence of solvent on the alumina-promoted C3-alkylation of indoles with α,β-unsaturated ketones. We found that lipophilic solvents were generally superior to hydrophilic ones with hexanes offering the 3-alkyl indole products in high yields. Thus, we demonstrate an inexpensive and procedurally simple new process that pairs acidic alumina with hexanes to achieve this important Michael alkylation. The substrate scope includes twenty-four examples with reaction yields ranging from 61 to 96%. (Figure presented.).
• Zhang, Xiong,Jones-Mensah, Ebenezer,Deobald, Jackson,Magolan, Jakob
• supporting information

  p. 5548 - 5551

  (2019/11/19)
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• Photocatalytic, Phosphoranyl Radical-Mediated N-O Cleavage of Strained Cycloketone Oximes
• A photoinduced, phosphoranyl radical-mediated protocol for the direct N-O cleavage of strained cycloketone oximes via a polar/SET crossover process was developed for the first time. This visible-light-driven direct N-O activation mode for oxime offers beneficial features such as streamlined synthetic process and versatile photochemical reactivities. Consequently, the alkenes and α-trifluoromethyl alkenes with varied electronic and structural features acted as competent radical receptors in this protocol, enabling facile accesses to a range of elongated cyano and/or gem-difluoroalkene-bearing compounds.
• Xia, Peng-Ju,Ye, Zhi-Peng,Hu, Yuan-Zhuo,Song, Dan,Xiang, Hao-Yue,Chen, Xiao-Qing,Yang, Hua
• supporting information

  p. 2658 - 2662

  (2019/04/25)
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• Heterogeneous gold-catalyzed oxidative cross-coupling of propargylic acetates with arylboronic acids leading to (E)-α-arylenones
• An efficient heterogeneous gold-catalyzed oxidative cross-coupling of propargylic acetates with arylboronic acids has been developed that proceeds smoothly in the presence of Selectfluor and provides a general and powerful tool for the preparation of various valuable α-arylenones with moderate to good yields, excellent E-selectivity, and recyclability of the gold catalyst. The reaction is the first example of heterogeneous gold-catalyzed arylative rearrangement of propargylic acetates for construction of complex enones.
• Liu, Dayi,Nie, Quan,Zhang, Rongli,Cai, Mingzhong
• supporting information

  p. 29 - 34

  (2018/11/30)
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• Method for synthesizing alpha,beta-unsaturated ketone compounds from dimethyl sulfoxide and ketone compounds
• The invention discloses a method for synthesizing alpha,beta-unsaturated ketone compounds from dimethyl sulfoxide and ketone compounds. According to the method, dimethyl sulfoxide and ketone compoundsare subjected to a one-pot reaction in the presence of carboxylate and persulfate so as to produce the alpha,beta-unsaturated ketone compounds. The method uses dimethyl sulfoxide as a methylenation reagent and employs a one-pot process for high-selectivity high-yield synthesis of the alpha,beta-unsaturated ketone compounds from the ketone compounds; and the method is simple to operate, low in cost, friendly to environment and beneficial for industrial production.
• -
• Paragraph 0047-0049; 0158-0161

  (2018/03/24)
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• A methylene compound of preparation method and its application (by machine translation)
• The invention discloses a methylene compound of preparation method and its application, relates to the field of organic synthesis, the process comprises: 1) in the presence of a three-valent metal salt catalyst, will arone compound and halogen methyl radical trialkyl ammonium salt dissolved in a solvent, 2) 80 - 130 °C reaction 1 - 4 hours, separated and purified α - the methyl radical is fragrant compounds, the reaction environment pollution is small, substrate and wide range of application. (by machine translation)
• -
• Paragraph 0023-0024; 0031-0032; 0071-0072

  (2017/11/16)
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• Transition Metal-Free α-Csp3-H Methylenation of Ketones to Form C=C Bond Using Dimethyl Sulfoxide as Carbon Source
• A direct α-Csp3-H methylenation of arylketones to form C=C bond using dimethyl sulfoxide as one-carbon source is achieved under transition metal-free reaction condition. Various aryl ketone derivatives react readily with DMSO, producing the α,β-unsaturated carbonyl compounds in yields of 42 to 90%. This method features a transition metal-free reaction condition, wide substrate scope and using DMSO as novel one-carbon source to form C=C bond, thus providing an efficient and expeditious approach to an important class of α,β-unsaturated carbonyl compounds. Based on the preliminary experiments, a plausible mechanism of this transformation is disclosed.
• Liu, Yu-Feng,Ji, Peng-Yi,Xu, Jing-Wen,Hu, Yu-Qun,Liu, Qiang,Luo, Wei-Ping,Guo, Can-Cheng

• p. 7159 - 7164

  (2017/07/26)
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• Domino Meyer-Schuster/Arylation Reaction of Alkynols or Alkynyl Hydroperoxides with Diazonium Salts Promoted by Visible Light under Dual Gold and Ruthenium Catalysis
• A method for the arylative coupling of alkynols or alkynyl hydroperoxides using equimolar amounts of diazonium salts at room temperature has been achieved through application of a gold/photoredox dual catalytic system. The excess of external reagents (oxi
• Alcaide, Benito,Almendros, Pedro,Busto, Eduardo,Luna, Amparo

• p. 1526 - 1533

  (2016/05/19)
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• A triphenylphosphine mediated photo-rearrangement and methanol addition of aryl chalcones to 1-propanones
• Aryl chalcones rearrange and add methanol to give substituted propane-1-ones upon UV-A irradiation in the presence of PPh3. We propose two possible mechanisms for this photo-rearrangement. The reaction involves either the formation of a phosphi
• Sun, Qiu,Yao, Chang Jiang,K?nig, Burkhard

• p. 948 - 952

  (2015/05/20)
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• Metal-free, one-pot, sequential protocol for transforming ,-epoxy ketones to -hydroxy ketones and -methylene ketones
• A new sequential, one-pot protocol for transforming 1,3-disubstituted 2,3-epoxy ketones to β;-hydroxy ketones and α-methylene ketones has been developed. Reaction of epoxy ketones with boron trifluoride etherate (BF3·OEt2) generates the cationic intermediates by regioselective epoxide ring opening and an acyl shift. Then, a treatment of these cations with 2-aryl-1,3-dimethylbenzimidazolines (DMBIH) results in formation of 1,2-disubstituted 3-hydroxy ketones. DMBIH serves as a hydride donor in the second step of this process. Finally, the β;-hydroxy ketones can be converted to 1,2-disubstituted 2-methylene ketones by treatment with methanesulfonic acid or a combination of methanesulfonyl chloride and triethylamine. Importantly, the sequential steps involved in formation of the α-methylene ketone products can be carried out in one pot.
• Hasegawa, Eietsu,Arai, Saki,Tayama, Eiji,Iwamoto, Hajime

• p. 1593 - 1600

  (2015/02/19)
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• Oxa-Michael addition promoted by the aqueous sodium carbonate
• An efficient Michael addition of alcohols to activated alkenes promoted by sodium carbonate with water as reaction medium has been developed. The reaction provides a general, economical and environmentally friendly approach for the synthesis of β-alkoxycarbonyl compounds.
• Guo, Shi-Huan,Xing, Sheng-Zhu,Mao, Shuai,Gao, Ya-Ru,Chen, Wen-Liang,Wang, Yong-Qiang
• supporting information

  p. 6718 - 6720

  (2014/12/11)
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• Palladium-catalyzed dehydrogenative β-arylation of simple saturated carbonyls by aryl halides
• (Chemical Equation Presented) A versatile palladium-catalyzed synthesis of highly substituted α,β-unsaturated carbonyl compounds has been developed. In contrast to the known Heck-type coupling reaction of unsaturated carbonyl compounds with aryl halides, the present methodology allows the use of stable and readily available saturated carbonyl compounds as the alkene source. In addition, the reaction proceeds well with low catalyst loadings and does not require any expensive metal oxidants or ligands. A variety of saturated aldehydes, ketones, and esters are compatible for the reaction with aryl halides under the developed reaction conditions to afford α,β-unsaturated carbonyl compounds in good to excellent yields. A possible reaction mechanism involves a palladium-catalyzed dehydrogenation followed by Heck-type cross couplings.
• Gandeepan, Parthasarathy,Rajamalli,Cheng, Chien-Hong

• p. 4485 - 4489

  (2015/01/09)
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• Copper-catalyzed arylative meyer-schuster rearrangement of propargylic alcohols to complex enones using diaryliodonium salts
• Free choice: A copper-catalyzed arylative Meyer-Schuster rearrangement is described. The reaction is compatible with a range of substituted propargylic alcohols and diaryliodonium salts and delivers complex trisubstituted enone products selectively as the
• Collins, Beatrice S. L.,Suero, Marcos G.,Gaunt, Matthew J.
• supporting information

  p. 5799 - 5802

  (2013/06/27)
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• Copper-catalyzed regioselective reaction of internal alkynes and diaryliodonium salts
• The copper-catalyzed highly regioselective reaction of internal alkynes with diaryliodonium salts was achieved for the first time. α-Arylketones were obtained in moderate to good yields from arylpropargylic alcohols or aryl alkyl alkynes under mild condit
• Xu, Ze-Feng,Cai, Chen-Xin,Liu, Jin-Tao
• supporting information

  p. 2096 - 2099

  (2013/06/05)
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• Modified shapiro reactions with bismesitylmagnesium as an efficient base reagent
• Bismesitylmagnesium has been shown to successfully mediate the Shapiro reaction. A range of tosylhydrazones has been subjected to the developed system, which furnishes exceptionally high incorporation of the introduced electrophiles and good yields of the functionalized styrenes. At conveniently accessible temperatures and with a comparably small excess of base reagent, this protocol offers an efficient alternative to the lithium-mediated process. Importantly, 1.05 equiv of Weinreb amides are sufficient to obtain aryl enones in good yields.
• Kerr, William J.,Morrison, Angus J.,Pazicky, Marek,Weber, Tina

• p. 2250 - 2253

  (2012/06/30)
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• Synthesis of pyrazolines by a site isolated resin-bound reagents methodology
• The elaboration of biologically important 3,4-substituted pyrazolines was achieved by an organocatalysed aza-Michael/transimination domino sequence between hydrazones and enones making use of a mixture of heterogeneous resin-bound acid/base reagents. This methodology nicely illustrates the site isolation concept of supported reagents allowing the simultaneous use of otherwise destructive reactive functionalities. The Royal Society of Chemistry 2010.
• Gembus, Vincent,Bonnet, Jean-Jacquesrouen,Janin, Franoisrouen,Bohn, Pierre,Levacher, Vincent,Briere, Jean-Franois
• supporting information; experimental part

  p. 3287 - 3293

  (2010/08/21)
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• Palladium-catalyzed carbonylation/acyl migratory insertion sequence
• Chemical Equation Presented On the move: A palladium-catalyzed reaction of aryl iodides, diazo compounds or N-tosylhyd razones, and carbon monoxide affords β-oxo esters or ketones/ enones (see scheme; DCE = l,2-dichloroethane). The products are delivered with high efficiency through the title sequence.
• Zhang, Zhenhua,Liu, Yiyang,Gong, Mingxing,Zhao, Xiaokun,Zhang, Yan,Wang, Jianbo
• supporting information; experimental part

  p. 1139 - 1142

  (2010/05/02)
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• Deoxybenzoins from Stille carbonylative cross-couplings using molybdenum hexacarbonyl
• Stille-type carbonylative cross-couplings, employing palladium catalysis and Mo(CO)6 as the carbon monoxide carrier, were used for the preparation of deoxybenzoins. Straightforward transformations were conveniently performed in closed vessels at 100 °C, providing the products in good yields. Benzyl bromides and chlorides were used as coupling partners with aryl and heteroaryl stannanes. This mild three-component carbonylation employs the destabilizing agent DBU to promote smooth release of carbon monoxide from Mo(CO)6, which made this protocol operationally simple and minimized the formation of Stille diarylmethane products.
• S?vmarker, Jonas,Lindh, Jonas,Nilsson, Peter
• scheme or table

  p. 6886 - 6889

  (2011/03/17)
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• Palladium-catalyzed coupling reaction of -diazocarbonyl compounds with aromatic boronic acids or halides
• Efficient palladium-catalyzed cross-coupling reactions of -diazocarbonyl compounds and arylboronic acids or aryl halides have been developed. The reaction proceeds smoothly for a range of diazo compounds, boronic acids, and halides. The coupling reaction conditions tolerate various substituents on the aromatic rings of the substrates, such as chloro, fluoro, acyl, oxo, ester, and nitro groups. This coupling reaction constitutes a novel access to -aryl-substituted ,-unsaturated carbonyl compounds. Mechanistically, palladium-carbene is supposed to be the key intermediate; its formation is followed by migratory insertion of an aryl group to the carbenic carbon of the palladium-carbene complex and subsequent -hydride elimination. Kinetic isotope effect (KIE) data measured for intra- and intermolecular competition experiments suggest that -hydride elimination is not involved in the rate-determining step
• Peng, Cheng,Yan, Guobin,Wang, Yan,Jiang, Yubo,Zhang, Yan,Wang, Jianbo
• experimental part

  p. 4154 - 4168

  (2011/02/25)
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• Remote stereocontrol mediated by a sulfinyl group: Synthesis of allylic alcohols via chemoselective and diastereoselective reduction of γ-methylene δ-ketosulfoxides
• The efficiency of the sulfinyl group as a remote controller of the chemoselectivity and diastereoselectivity of the reduction of α,β-unsaturated α-[2-(p-tolylsulfinyl)phenyl] substituted ketones 1 has been demonstrated in reactions carried out under NaBH
• Ruano, Jose L. Garcia,Fernandez-Ibanez, M. Angeles,Fernandez-Salas, Jose A.,Maestro, M. Carmen,Marquez-Lopez, Pablo,Rodriguez-Fernandez, M. Mercedes
• supporting information; scheme or table

  p. 1200 - 1204

  (2009/07/18)
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• Rearrangement during halogenation of 2-hydroxy-1,2-diphenylpropan-1-one (α-methylbenzoin)
• The reaction of 2-hydroxy-1,2-diphenylpropan-1-one 1 with SOCl2 or PBr3 gives, respectively, the 3-chloro- and 3-bromo-1,2-diphenylpropan-1-ones 4 and 6. The expected 2-chloro- and 2-bromo-1,2-diphenylpropan-1-ones 2 and 5 can, howev
• Aitken, Kati M.,Alan Aitken

• p. 5217 - 5220

  (2008/09/21)
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• Palladium-catalyzed cross-coupling of α-diazocarbonyl compounds with arylboronic acids
• Pd(PPh3)4-catalyzed reaction between α-diazocarbonyl compounds and arylboronic acids leads to the formation of cross-coupling products in good yields. Copyright
• Peng, Cheng,Wang, Yan,Wang, Jianbo

• p. 1566 - 1567

  (2008/09/17)
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• 1,2-Addition of α,α,α-trichlorotoluene to ketones via a Mg Barbier reaction in DMF: New route to cycloalk-1-en-1-yl and alk-1-en-1-yl phenyl ketones
• The reductive cyclocondensation of α,α,α-trichlorotoluene to enolisable ketones enables the preparation of (cyclo)alken-1-en-1-yl phenyl ketones via the formation of an intermediate chlorooxirane. Copyright Taylor & Francis Group, LLC.
• Aaziz, Akima,Oudeyer, Sylvain,Leonel, Eric,Paugam, Jean Paul,Nedelec, Jean-Yves

• p. 1147 - 1154

  (2008/02/01)
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• Efficient synthesis of functionalized organozinc compounds by the direct insertion of zinc into organic iodides and bromides
• (Chemical Equation Presented) Insider dealing: A wide range of poly-functional (hetero)aromatic and aliphatic zinc reagents can be easily prepared in THF. The compounds are formed by a Zn insertion reaction mediated by the addition of LiCl (see scheme; All = allyl).
• Krasovskiy, Arkady,Malakhov, Vladimir,Gavryushin, Andrei,Knochel, Paul

• p. 6040 - 6044

  (2007/10/03)
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• Dibromomethane as one-carbon source in organic synthesis: Microwave-accelerated α-methylenation of ketones with dibromomethane and diethylamine
• The reactivity of aryl alkyl ketone with a preheated mixture of dibromomethane and diethylamine is poor and gives an α-methylenation product in very low yield even under refluxing condition. It can be accelerated dramatically by microwave irradiation. Under microwave condition, the cyclic 1,3-dicarbonyls, aryl alkyl ketones, heteroaryl alkyl ketones and acyclic benzyl ketone give α-methylenation products in modest to good yields.
• Hon, Yung-Son,Hsu, Tzyy-Rong,Chen, Chun-Yan,Lin, Yi-Hui,Chang, Fong-Jong,Hsieh, Cheng-Han,Szu, Ping-Hui

• p. 1509 - 1520

  (2007/10/03)
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• Synthesis of 2-alkyl (and aryl)-1-aryl-2-propen-1-ones via m-CPBA mediated oxidation of γ-(benzotriazol-1-yl)allylic selenides
• Treatment of 2-alkyl (and aryl)-3-aryl-3-(benzotriazol-1-yl)allylic selenides with m-CPBA (1 equiv.) for 10 min in CH2Cl2 at rt gave 2-alkyl (and aryl)-1-aryl-2-propen-1-ones in excellent yields.
• Kim, Taehoon,Kim, Kyongtae

• p. 3021 - 3024

  (2007/10/03)
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• Specific C-C coupling of the labile diruthenium bridging methylene complex, Cp2Ru2(μ-CH2)(CO)2(MeCN), with diazoalkanes (R2C=N2) leading to alkenyl complexes, Cp2Ru2(μ-CH=CR2)(μ-H)(CO)2, and alkenes, CH2=CR2
• Treatment of the labile μ-methylene species, Cp2Ru2(μ-CH2)(CO)2(MeCN) 1, with diazoalkanes results in C-C coupling of the alkylidene units. The reaction of monosubstituted diazoalkanes (N2=CHR) and 4-t-butyldiazocyclohexane gives the μ-alkenyl-μ-hydride complexes, Cp2Ru2(μ-CH=CR2)(μ-H)(CO)2 2, as sole products, whereas the reaction of disubstituted aryldiazoalkanes (N2=CR1R2) produces olefins (CH2=CR1R2) together with mixtures of unidentified organometallic compounds. Labeling experiments using 1-d2 (μ-CD2) and 1-13C (μ-13CH2) reveal that the methylene bridge in 1 is converted to the α-CH and μ-H parts in 2 and the alkylidene part of diazoalkane is incorporated into the β-CR2 part of the alkenyl bridge. The olefinic products should come from a η2-olefin intermediate, Cp2Ru2(η2CH2=CHR)(CO) 2 7, resulting from coupling of the two alkylidene fragments within the coordination sphere of the diruthenium core. It is notable that C-H oxidative addition in 7 takes place prior to free rotation of the η2-olefin ligand as judged by the regiospecificity of the labeling experiments. Thus specific coupling of alkylidene units proceeds under mild conditions and this C-C coupling reaction serves as a model system for the carbon chain propagation step of surface-catalyzed reactions such as catalytic CO hydrogenation.
• Akita, Munetaka,Hua, Ruimao,Knox, Selby A.R.,Moro-Oka, Yoshihiko,Nakanishi, Sadahiro,Yates, Michael I.

• p. 71 - 83

  (2007/10/03)
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• Superacid-catalyzed electrocyclization of 1-phenyl-2-propen-1-ones to 1- indanones. Kinetic and theoretical studies of electrocyclization of oxonium- carbenium dications
• Strongly acidic conditions are required to induce the Nazarov-type cyclization of aryl vinyl ketones, although chemical analogy with the Nazarov reaction would superficially imply a straightforward electrocyclization reaction of the O-protonated monocation. In this paper we describe the superacid-catalyzed prototype cyclization of 1-phenyl-2-propen-1-ones. The acidity dependence of these cyclization reactions as revealed by kinetic measurements strongly suggests the involvement of the O,O-diprotonated dication rather than the O-protonated monocation. That is the cyclization of 1-phenyl-2-propen-1-ones represents an electrocyclization of the oxonium- carbenium dication. We also describe the effect of substituents at the 2- position of 1-phenyl-2-propen-1-ones. Ab initio calculations, based on the density functional theory, support the idea that electrocyclization of the dication is energetically more favarable than that of the monocation.
• Suzuki, Takayoshi,Ohwada, Tomohiko,Shudo, Koichi

• p. 6774 - 6780

  (2007/10/03)
• 

• Acid-catalyzed Reactions of 1,2-Dicarbonylethanes with Benzene. Ethylene Dication Electrophiles.
• 1,2-dicarbonyl compounds reacted with benzene in the presence of a strong acid, trifluoromethanesulfonic acid, to give gem-diphenylated ketones in high yields.The reaction was accelerated when the acidity of the medium was increased, supporting involvement of O,O-diprotonated 1,2-dicarbonyl species (i.e., 1,2-dihydroxyethylene dications) as the active electrophiles.
• Yamazaki, Takahisa,Saito, Shin-ichi,Ohwada, Tomohiko,Shudo, Koichi

• p. 5749 - 5752

  (2007/10/02)
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• A convenient alternative route to β-aminoketones
• Enaminones has been prepared and submitted to conjugate reduction with LAH and the system Al2O3/R2NH to give β-aminoketones. The latter tandem amination system has also been applied in the Mannich reaction, improving the synthesis of several new diaryl β-aminoketones. Besides, the sequential use of DMFDMA and LAH-CuI on deoxybenzoins furnishes a new route for the synthesis of enones.
• San Martin,De Marigorta,Dominguez

• p. 2255 - 2264

  (2007/10/02)
• 

• Hypervalent iodine oxidation of allenes: Synthesis of 3-acetoxy-3-alkoxypropynes, 2-alkoxy-3-tosyloxypropanals and phenyl-substituted propenals and propenones
• 1-Alkoxyallenes yield 3-acetoxy-3-alkoxypropynes upon oxidation with [(diacetoxy)iodo]benzene at -78°C in dichloromethane. Treatment with [hydroxy(tosyloxy)iodo]benzene under similar conditions gives 2-alkoxy-3-tosyloxypropanals. Phenyl-substituted propen
• Moriarty,Hopkins,Vaid,Vaid,Levy

• p. 847 - 849

  (2007/10/02)
• 

• METHOXYMETHYL METHYL SULFATE - A NEW REAGENT FOR THE FUNCTIONALIZATION OF OLEFINS AND ACETYLENES
• The reaction of methylenecyclobutane, styrene, 1-hexene, and phenyl- and diphenylacetylenes with methoxymethyl methyl sulfate, generated in situ from methylal and sulfur trioxide, takes place as conjugate addition of the methoxymethyl and methyl sulfate groups and leads to the respective alkoxymethyl sulfates in the case of olefins and vinyl methyl sulfates in the case of acetylenes.The high reactivity of the obtained compounds in reactions with nucleophiles was used for the synthesis of diethers, unsaturated ethers, and acetoxy and α,β-unsaturated ketones.
• Lebedev, M. Yu.,Balenkova, E. S.

• p. 1214 - 1219

  (2007/10/02)
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• Cathodic Addition of Benzylidyne Trichloride to Ketones and Aldehydes
• Ketones are converted to homologated enones 7a-g in good yields by cathodic addition of benzylidyne trichloride (1d).As intermediates α-Chlorooxiranes 6 are assumed, which rearrange via α-keto carbenium ions 9 to enones.The intermediacy of 9 is supported by the addition of 1d to norcamphor, where the products indicate equilibrating norbornyl cations as intermediates. α,β-Unsaturated ketones lead depending on steric shielding of the double bond to the cyclopropane 23 as 1,4-adduct or the enone 26 as 1,2-adduct.With aldehydes and 1d, α-chloro or βhydroxy ketones, the conversion products of 2-chlorooxiranes, are obtained.
• Steiniger, Michael,Schaefer, Hans J.

• p. 125 - 132

  (2007/10/02)
• 

• PREPARATION OF ACYCLIC α-METHYLENE KETONES: PALLADIUM-CATALYZED COUPLING OF ACID CHLORIDES WITH ORGANOTIN REAGENTS
• The reaction of organotin reagents with acid chlorides, catalyzed by palladium (0), provides a general entry to α-substituted unsaturated ketones.
• Renaldo, A. F.,Ito, Hiroshi

• p. 1823 - 1830

  (2007/10/02)
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• An Efficient and Convenient Method for the Preparation of α-Methylenated Ketones from Silyl Enol Ethers
• In the presence of a catalytic amount of stannous halide, silyl enol ethers react with bromomethyl methyl ether to give the corresponding α-bromoethyl ketones, which are smoothly converted to α-methylenated ketones on the successive addition of tertiary amine by one-pot procedure.This method is successfully applied to a synthesis of sarkomycin intermediate.
• Hayashi, Masaji,Mukaiyama, Teruaki

• p. 1283 - 1286

  (2007/10/02)
• 

• A CONVENIENT SYNTHESIS OF 1H-1,2,4-TRIAZOL-1-YL-PROPAN-3-ONE DERIVATIVES BY MODIFIED MANNICH REACTION
• 1H-1,2,4-Triazol-yl-propan-3-ones were synthesized regioselectively using a modified Mannich reaction.Reactions of enones and Mannich bases with imidazole are also described.
• Takahashi, Kimio,Shimizu, Sumio,Ogata, Masaru

• p. 809 - 816

  (2007/10/02)
• 

• Monoozonolyses of Acyclic Conjugated Dienes
• Monoozonolyses of isoprene (1a), 2-methyl-3-phenyl-1,3-butadiene (1b), 2,3-diphenyl-1,3-butadiene (25), and 2,3,4,5-tetramethyl-2,4-hexadiene (34) have been examined in pentane and in methanol.The dienes 1a, b and 25 afforded all possible α,β-unsaturated monoozonides and α,β-unsaturated methoxy hydroperoxides, respectively, whereas diene 34 gave no ozonide and no α,β-unsaturated methoxy hydroperoxide.From the dienens 25 and 34, the corresponding monoepoxides have been formed additionally.The results allow some conclusions concerning the regioselectivity of ozone attack at the unsymmetrically substituted dienes 1a, b as well as concerning the cleavage directions of primary ozonides.
• Griesbaum, Karl,Zwick, Gerhard

• p. 3041 - 3057

  (2007/10/02)
• 

• α-KETOCARBONIUM IONS - EVIDENCE FOR NOVEL OXO-TRANSFER
• Evidence from specifically labelled acylcarbenium ion of an oxo-transfer reaction is reported.
• Maleki, Mehran,Hopkinson, Alan C.,Lee-Ruff, Edward

• p. 4911 - 4912

  (2007/10/02)
• 

• The Chemistry of Aryllead Tricarboxylates. Synthesis of Some α-Aryl α,β-Unsaturated Carbonyl Compounds
• The treatment of 4-benzoyltetrahydrofuran-2,3-dione (2a) with 2 equiv. of phenyllead triacetate (3a) in chloroform gives 1,2-diphenylpropenone (4a) in excellent yield.This reaction has been investigated with a number of similar derivatives of tetrahydrofuran-2,3-dione and a number of aryllead triacetates.It has been found to be very sensitive to the nature of the substituent at C4, and it would appear to be limited to the synthesis of α-methylene carbonyl compounds since a 5-methyl substituent inhibits the reaction.
• Kopinski, Richard P.,Pinhey, John T.

• p. 311 - 316

  (2007/10/02)
•