- Pd-catalyzed oxidative Heck-type arylation of vinyl ketones, alkenes, and acrylates with Sb-aryl-tetrahydrodibenz[c,f][1,5]azastibocines
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The Pd-catalyzed cross-coupling reactions of Sb-aryl-1,5-azastibocines with alkenes are described. The reactions of azastibocines with alkenes such as vinyl ketones, alkenes, and acrylates in the presence of 10 mol% PdCl2 at 80 °C in DMA under aerobic conditions produced Heck adducts in moderate-to-excellent yields. Single-crystal X-ray and NMR analysis revealed that the aryl donors in this reaction, the Sb-aryl-1,5-azastibocines, are hypervalent compounds that display N–Sb intramolecular non-bonding interaction. These are the first examples of Pd-catalyzed Heck-type arylations using heterocyclic hypervalent organoantimony compounds. Although the reactions proceeded efficiently with the azastibocines, they hardly progressed with trivalent and pentavalent triarylantimony reagents.
- Murata, Yuki,Kakusawa, Naoki,Arakawa, Yukako,Hayashi, Yukako,Morinaga, Shun,Ueda, Masaaki,Hyodo, Tadashi,Matsumura, Mio,Yamaguchi, Kentaro,Kurita, Jyoji,Yasuike, Shuji
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- Iterative synthesis of alkenes by insertion of lithiated epoxides into boronic esters
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The insertion of lithiated epoxides into boronic esters followed by thermal syn-elimination provides a stereospecific entry to alkenes. This process avoids transition metals and is amenable to iteration to provide higher substitution patterns.
- Bojaryn, Kevin,Fritsch, Stefan,Hirschhaüser, Christoph
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supporting information
p. 2218 - 2222
(2019/04/10)
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- Palladium/Light induced radical alkenylation and allylation of alkyl iodides using alkenyl and allylic sulfones
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Alkenylation and allylation of alkyl iodides with alkenyl and allyl sulfones, respectively, took place under Pd/photoirradiation system. The initial alkyl radical, derived from a single electron transfer between Pd(0) and RI, underwent the title transformations. Pd(0) was regenerated through a reductive elimination of PhSO2PdI, which is formed by the combination of the sulfonyl radical and the palladium radical. The addition of water was effective, presumably by pushing the equilibrium through hydrolysis of PhSO2I.
- Sumino, Shuhei,Uno, Misae,Huang, Hsin-Ju,Wu, Yen-Ku,Ryu, Ilhyong
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supporting information
p. 1078 - 1081
(2018/02/23)
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- Metal-Catalyzed Remote Functionalization of ω-Ene Unsaturated Ethers: Towards Functionalized Vinyl Species
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The combined ruthenium-catalyzed chain walking with the nickel-catalyzed cross-coupling reaction of ω-alkenyl ethers provide a unique entry to functionalized vinyl species. This transformation illustrates the power and flexibility of remote functionalization by demonstrating the compatibility of two independent reactions involving unrelated sites.
- Ho, Guo-Ming,Judkele, Lina,Bruffaerts, Jeffrey,Marek, Ilan
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p. 8012 - 8016
(2018/06/29)
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- N-Acylsaccharins as Amide-Based Arylating Reagents via Chemoselective N-C Cleavage: Pd-Catalyzed Decarbonylative Heck Reaction
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Palladium-catalyzed decarbonylative Heck reaction of amides by chemoselective N-C activation using N-acylsaccharins as coupling partners has been accomplished. These studies represent only the second example of amide-Heck reactions reported to date. A broad range of electronically diverse amide and olefin coupling partners is amenable to this transformation. Orthogonal site-selective Heck cross-couplings by C-Br/N-C cleavage and mechanistic studies are reported. This report introduces readily available, bench-stable, cheap, and benign N-acylsaccharins as aryl transfer reagents to access versatile aryl-metal intermediates.
- Liu, Chengwei,Meng, Guangrong,Szostak, Michal
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p. 12023 - 12030
(2016/12/09)
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- Z -selective olefin synthesis via iron-catalyzed reductive coupling of alkyl halides with terminal arylalkynes
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Selective catalytic synthesis of Z-olefins has been challenging. Here we describe a method to produce 1,2-disubstituted olefins in high Z selectivity via reductive cross-coupling of alkyl halides with terminal arylalkynes. The method employs inexpensive and nontoxic catalyst (iron(II) bromide) and reductant (zinc). The substrate scope encompasses primary, secondary, and tertiary alkyl halides, and the reaction tolerates a large number of functional groups. The utility of the method is demonstrated in the synthesis of several pharmaceutically relevant molecules. Mechanistic study suggests that the reaction proceeds through an iron-catalyzed anti-selective carbozincation pathway.
- Cheung, Chi Wai,Zhurkin, Fedor E.,Hu, Xile
-
supporting information
p. 4932 - 4935
(2015/05/05)
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- Palladium-catalyzed heck-type cross-couplings of unactivated alkyl iodides
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A palladium-catalyzed, intermolecular Heck-type coupling of alkyl iodides and alkenes is described. This process is successful with a variety of primary and secondary unactivated alkyl iodides as reaction partners, including those with hydrogen atoms in t
- McMahon, Caitlin M.,Alexanian, Erik J.
-
supporting information
p. 5974 - 5977
(2014/06/10)
-
- Synthesis and structure of cobalt(II) iodide bearing a bulky N-heterocyclic carbene ligand, and catalytic activation of bromoalkanes
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A divalent cobalt iodine complex bearing 1,3-bis(mesityl)imidazol-2-ylidene and pyridine ligands was synthesized and its structure was determined. The cobalt center has a typical d7-tetrahedral geometry, as expected. Catalytic application of this cobalt complex with bromoalkanes and Grignard reagents demonstrated high-yield formation of alkenes as a result of β-hydrogen elimination; in sharp contrast, the activation of alkyl halides was not successful using the larger N-heterocyclic carbene ligand, 1,3-bis(2,6-diisopropyl-phenyl)imidazol-2-ylidene. In the presence of styrene, Heck reaction proceeded with trans selectivity. The reaction of a substrate containing a bromobenzyl moiety yielded a homocoupling product.
- Matsubara, Kouki,Kumamoto, Aya,Yamamoto, Hitomi,Koga, Yuji,Kawata, Satoshi
-
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- Pd-catalyzed cross-coupling reactions exhibiting catalyst turnover numbers (TONs) exceeding one million
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Pd-catalyzed cross-coupling giving aryl-aryl, alkenyl-aryl, aryl-alkenyl, alkynyl-aryl, and alkynyl-alkenyl products exhibited ultra-high turnover numbers (TONs) of 0.7×107~0.69×109 by using organozincs generated in situ by treatment of the corresponding organolithiums with dry ZnBr2. Additionally, the hydrozirconation.Pd-catalyzed cross-coupling tandem processes via treatment of 1-alkynes with iBu2AlH-ZrCp2Cl2 followed by selective (≥98%) alkenyl.alkenyl coupling with either (E)- or (Z)-ethyl 3-bromoacrylate exhibited high TONs of 0.9×105~0. 81×107. Furthermore, Pd-catalyzed cross-coupling of 2-thienylzinc bromide and 1-iodo-4-nitrobenzene also showed a high TON of 0.87×105. ARKAT-USA, Inc.
- Xu, Shiqing,Truex, Nicholas L.,Mohan, Swathi,Negishi, Ei-Ichi
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p. 242 - 252
(2013/01/16)
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- Preparation of alkylmagnesium reagents from alkenes through hydroboration and boron-magnesium exchange
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Tolerant: Alkylmagnesium reagents can be synthesized from alkenes through a sequence of hydroboration and subsequent boron-magnesium exchange using a method that tolerates different functional groups (see scheme). The resulting alkylmagnesium reagents can be used in carbon-carbon bond forming reactions, such as alkylation reactions or transition-metal-catalyzed cross-coupling reactions. Copyright
- Reichle, Markus A.,Breit, Bernhard
-
supporting information; experimental part
p. 5730 - 5734
(2012/08/14)
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- Copper-catalyzed alkene arylation with diaryliodonium salts
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Alkenes and arenes represent two classes of feedstock compounds whose union has fundamental importance to synthetic organic chemistry. We report a new approach to alkene arylation using diaryliodonium salts and Cu catalysis. Using a range of simple alkenes, we have shown that the product outcomes differ significantly from those commonly obtained by the Heck reaction. We have used these insights to develop a number of new tandem and cascade reactions that transform readily available alkenes into complex arylated products that may have broad applications in chemical synthesis.
- Phipps, Robert J.,McMurray, Lindsay,Ritter, Stefanie,Duong, Hung A.,Gaunt, Matthew J.
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supporting information; experimental part
p. 10773 - 10776
(2012/08/07)
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- Iridium as a general catalyst for the decarbonylative addition of aldehydes to alkynes
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A general catalytic system for the decarbonylative addition reaction of aldehydes with alkynes is developed by using an iridium catalyst system. Both aromatic and aliphatic aldehydes reacted with terminal alkynes efficiently to give the corresponding olefination products in high yields and up to 11:1 E/Z selectivity.
- Wang, Jun,Guo, Xiangyu,Li, Chao-Jun
-
supporting information; experimental part
p. 211 - 215
(2011/02/17)
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- Iron-catalyzed desulfinylative C-C cross-coupling reactions of sulfonyl chlorides with grignard reagents
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(Chemical Equation Presented) A friendly couple: Conditions have been uncovered that allow the desulfinylative C-C cross-coupling reaction of inexpensive sulfonyl chlorides and Grignard reagents (see scheme, acac = acetylacetonate, NMP = N-methylpyrrolidone). The reactions rely on environmentally friendly iron catalysts and do not require expensive and/or toxic ligands.
- Rao Volla, Chandra M.,Vogel, Pierre
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p. 1305 - 1307
(2008/12/22)
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- Palladium-tetraphosphine catalysed heck reaction with simple alkenes: Influence of reaction conditions on the migration of the double bond
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The Heck reaction of aryl halides with simple alk-1-enes is a powerful method for the synthesis of (E)-1-arylalk-1-ene derivatives. The major problem of this reaction is the palladium-catalysed migration of the carbon-carbon double bond along the alkyl ch
- Fall, Yacoub,Berthiol, Florian,Doucet, Henri,Santelli, Maurice
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p. 1683 - 1696
(2008/02/08)
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- Copper catalyzed magnesium-Barbier reaction for γ-selective alkyl-allyl coupling
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CuCN catalyzed alkyl-allyl coupling under magnesium-Barbier conditions occurs regioselectively and affords predominantly the γ-products in good to high yields. This one-pot CuCN catalyzed reaction utilising Mg, an alkyl halide and an allylic substrate in THF at room temperature provides an easy alternative to the classical CuCN catalyzed γ-allylation of alkyl Grignard reagents.
- Erdik, Ender,Ko?o?lu, Melike
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p. 4211 - 4214
(2008/02/08)
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- From vinyl sulfides, sulfoxides and sulfones to vinyl zirconocene derivatives
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An easy and straightforward new method for the preparation of sp 2 zirconocene derivatives from a wide range of heterosubstituted alkenes such as vinyl sulfides, sulfoxides and sulfones is described. In all cases, a complete isomerization of the stereochemistry is observed and only the E-isomer is obtained. The reactivity of the resulting vinylic organometallic can be increased by a transmetalation reaction into organocopper, organozinc or organopalladium species and, therefore, several carbon-carbon formation were easily realized.
- Farhat, Shahera,Zouev, Irena,Marek, Ilan
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p. 1329 - 1337
(2007/10/03)
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- Cobalt(I)-catalyzed stereoselective olefination of alkylzinc reagents with aldehydes
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The efficient olefination from organozinc reagents with aldehydes is exploited in a new synthesis of aryl and alkyl olefins.
- Wang, Jin-Xian,Fu, Ying,Hu, Yulai,Wang, Kehu
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p. 1506 - 1510
(2007/10/03)
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- Heck reaction of aryl halides with linear or cyclic alkenes catalysed by a tetraphosphine/palladium catalyst
-
cis,cis,cis-1,2,3,4-Tetrakis(diphenylphosphinomethyl)cyclopentane/[PdCl(C 3H5)]2 system catalyses efficiently the Heck reaction of aryl halides with linear alkenes such as pent-1-ene, oct-1-ene or dec-1-ene. Selectivities up to 70% in favour of E-1-arylalk-1-ene isomers can be obtained. In the presence of cyclic alkenes the selectivities of the reactions strongly depends on the ring size. Addition to cyclohexene or cycloheptene led mainly to 1-arylcycloalk-3-ene derivatives. On the other hand, addition to cyclooctene led to 1-arylcycloalk-1-ene adducts.
- Berthiol, Florian,Doucet, Henri,Santelli, Maurice
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p. 1221 - 1225
(2007/10/03)
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- Pd-Catalyzed Cross-Coupling Reaction of Alkyl Tosylates and Bromides with Grignard Reagents in the Presence of 1,3-Butadiene
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A new method for cross-coupling reaction of alkyl tosylates and bromides with Grignard reagents has been developed by the use of Pd(acac)2 or PdCl2 as the catalyst. Addition of 1,3-butadiene is essential to afford good yields of coupling products. This reaction proceeds efficiently at room temperature using primary and secondary alkyl and aryl Grignard reagents.
- Terao, Jun,Naitoh, Yoshitaka,Kuniyasu, Hitoshi,Kambe, Nobuaki
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p. 890 - 891
(2007/10/03)
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- Preparation and nickel-catalyzed coupling reactions of divinylic selenides
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The preparation of divinylic selenides by the reaction of selenium bis-phosphonate with aromatic aldehydes is described. The nickel-catalyzed cross coupling of the divinylic selenides with Grignard reagents was also studied.
- Silveira, Claudio C.,Santos, Paulo Cesar S.,Braga, Antonio L.
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p. 7517 - 7520
(2007/10/03)
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- From vinyl sulfides, sulfoxides, and sulfones to vinyl transition metal complexes
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A transformation with promising versatility: The vinyl zirconium complex 1 can be prepared readily in situ from the educts mentioned in the title and reacts with electrophiles, including other transition metal complexes, to give polysubstituted olefins (s
- Farhat, Shahera,Marek, Ilan
-
p. 1410 - 1413
(2007/10/03)
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- Synthesis of Z-alkenes from alkenylcatecholboranes through reaction with RMgX and I2 induced rearrangement
-
Addition of RMgX and BrMg(CH2)nMgBr reagents to alkenylcatecholborane followed by iodine induced rearrangement and oxidation provided Z-olefins and Z-olefinic alcohols in moderate to good yields. This procedure is advantageous over the previous methods of synthesis of Z-olefins from alkenylboranes since the alkyl groups which are not available through hydroborations can also be utilized.
- Periasamy, Mariappan,Bhanu Prasad,Suseela, Yantrapragada
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p. 2743 - 2748
(2007/10/02)
-
- Subsituted 4-(2-alkenylsulfinyl)morpholines : preparation and conversion into the corresponding sulfinic acids and esters. Stereochemistry of olefin formation by hydrolytic desulfinylation of allylic sulfinamides.
-
By reaction with 4-(chlorosulfenyl)morpholine in the presence of triethylamine, several substituted allylic alcohols have been converted into the title sulfinamides.As a complementary method, the new α-lithio allylic sulfinamides have been prepared and efficiently alkylated with organic halides.The boron trifluoride-etherate catalyzed treatment of the allylic sulfinamides with simple saturated alcohols provided the corresponding alkyl sulfinates while propargylic and allylic alcohols opened a route to various α,α'-bis-unsaturated sulfones.Efficient conditions for the acid-catalyzed hydrolysis of allylic sulfinamides are described and some allylic sulfinic acids bearing an electron-withdrawing group were isolated.Smooth fragmentation of the homoconjugated sulfinic acids gave the corresponding (E)-olefins stereoselectively. - Key words: sigmatropic rearrangement / allylic sulfinamide / allylic sulfinic ester / organolithium derivative / sulfone / retro-ene reaction / sulfur dioxide elimination / stereochemistry
- Baudin, Jean-Bernard,Julia, Sylvestre
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p. 196 - 214
(2007/10/02)
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- Stereochemistry of direct olefin formation from carbonyl compounds and lithiated heterocyclic sulfones
-
The conditions for the title reaction were studied for the 2-benzothiazole and 2-pyridine series and for some examples in the 2-pyrimidine series.The olefin preparations were generally observed to be more efficient for 2-BT-sulfone systems.From the data of the hundred cases studied, it can be concluded that (E)-olefins are obtained: (i) from saturated BT-sulfones and aromatic aldehydes; and (ii) from benzylic BT-sulfones and branched saturated aldehydes (isobutyraldehyde, pivalaldehyde) or α,β-ethylenic or aromatic aldehydes. (Z)-olefins arise: (i) fom propargylic BT-sulfones and saturated or aromatic aldehydes; and (ii) from allylic or benzylic Pyr-sulfones and saturated aldehydes.Possible mechanisms for this new olefination procedure were examined. - heteroaromatic sulfones, organolithium derivatives, intramolecular ipso reactions, stereochemistry, elimination, olefination.
- Baudin, J. B.,Hareau, G.,Julia, S. A.,Lorne, R.,Ruel, O.
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p. 856 - 878
(2007/10/02)
-
- Alkyliron and Alkylcobalt Reagents, III. - Nonstabilized Ironalkyls: Formation, Detection, and Chemoselectivity
-
The crystalline ate complex Me4FeLi2(Et2O)2 (1d) described in the literature as well as the complexes MeFeCl (1a), Me2Fe (1b), Me3FeLi (1c), nBu2Fe (2a), nBu4FeLi2 (2b), nOct2Fe (3a), nOct3FeLi (3b), and nOct4FeLi2 (3c) are prepared in situ by transmetallation of MeLi, nBuLi, and nOctLi with FeCl2 (readily available by in situ reduction of FeCl3 with MeLi).All these complexes have been subjected to reaction with organic substrates for the first time.Evidence for this transmetallation has been furnished by a novel test (referred to as "β-bromostyrene-ketone test").In this test, involving addition of β-bromostyrene (4) and 4-methylpentan-2-one (5), the alkyllithium compounds alkylate selectively only the ketone and the alkyliron compounds almost exclusively the β-bromostyrene.The high preference of the alkyliron reagents for the alkylation of the β-bromostyryl residue has been utilized for regioselective butylations and octylations of 1-phenyl>-ethanone (6).Moreover, in competition reactions with benzaldehydes/4-methylpentan-2-one the alkyliron reagents have been found to react usually specifically with aldehydes.The decomposition temperatures of the reagents 1a,b,c and 2b in THF have been determined to be 0, -10, 25, and -20 deg C, respectively.Key Words: Iron, organo reagents
- Kauffmann, Thomas,Laarmann, Barbara,Menges, Detlef,Neiteler, Gabriele
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p. 163 - 169
(2007/10/02)
-
- Facile Reduction of Dithiocarbonates Derived from Secondary Alcohols with n-Bu3SnH-Et3B and Synthesis of 2-Furanthiones and 2-Furanones by Intramolecular Addition of Alkoxythiocarbonyl Free Radicals to Acetylenic Linkages
-
The reduction of dithiocarbonates or thiocarbonates by n-Bu3SnH-Et3B easily gives the corresponding hydrocarbons.The intermediate alkoxythiocarbonyl radical equivalents are trapped by properly located carbon-carbon multiple bonds.The dithiocarbonates derived from either homopropargylic or homoallylic alcohols produce tetrahydrofuranones upon treatment with n-Bu3SnH-Et3B.Application of this new method to the conversion of carbonyl compounds into olefins is also described.
- Nozaki, Kyoko,Oshima, Koichiro,Utimoto, Kiitiro
-
p. 2578 - 2583
(2007/10/02)
-
- Palladium-Catalyzed Inter- and Intramolecular Cross-Coupling Reactions of B-Alkyl-9-borabicyclononane Derivatives with 1-Halo-1-alkenes or Haloarenes. Syntheses of Functionalized Alkenes, Arenes, and Cycloalkenes via a Hydroboration-Coupling Sequence
-
The cross-coupling reaction of B-alkyl-9-borabicyclononanes (B-R-9-BBN), readily obtainable from alkenes by hydroboration, with 1-halo-1-alkenes or haloarenes in the presence of a catalytic amount of PdCl2(dppf) and bases, such as sodium hydroxide, potassium carbonate, and phosphate, gave the corresponding alkenes or arenes.Because the reaction is tolerant of a variety of functionalities on either coupling partner, stereochemically pure functionalized alkenes and arenes can be obtained under mild conditions.The utility of the reaction was demonstrated by the stereoselective synthesis of 1,5-alkadienes (7 and 8) and the extension of a side chain in a steroid (11).The hydroboration of haloalkadienes (12), followed by the intramolecular cross-coupling, gave a short-step procedure for synthesis of cycloalkenes, benzo-fused cycloalkenes, and exocyclic alkenes (14 and 16).
- Miyaura, Norio,Ishiyama, Tatsuo,Sasaki, Hirotomo,Ishikawa, Masako,Satoh, Makoto,Suzuki, Akira
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p. 314 - 321
(2007/10/02)
-
- STEREOSELECTIUVE FORMATION OF (E)-OLEFINS HYDROLYTIC DESULPHINYLATION OF SOME SUBSTITUTED 4-(2'-ALKENESULPHINYL)-MORPHOLINES
-
The boron trifluoride-etherate catalysed hydrolysis of the title sulphinamides 1 provide olefins with (E:Z)-ratios depending on the nature of the substituents on the allylic chain.
- Baudin, Jean-Bernard,Julia, Silvestre A.
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p. 1967 - 1970
(2007/10/02)
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- FACILE REDUCTION OF DITHIOCARBONATES WITH n-Bu3SnH-Et3B. EASY ACCESS TO HYDROCARBONS FROM SECONDARY ALCOHOLS
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The reduction of dithiocarbonates or thiocarbonates by n-Bu3SnH-Et3B easily gives the corresponding hydrocarbons.Application of a new method in the conversion of carbonyl compounds into olefins is also described.
- Nozaki, Kyoko,Oshima, Koichiro,Utimoto, Kiitiro
-
p. 6125 - 6126
(2007/10/02)
-
- REACTIONS OF VINYLSILANES WITH LEWIS ACID-ACTIVATED IODOSYLBENZENE: STEREOSPECIFIC SYNTHESIS OF VINYLIODONIUM TETRAFLUOROBORATES AND THEIR REACTIONS AS HIGHLY ACTIVATED VINYL HALIDES
-
Alkenyl(phenyl)iodonium tetrafluoroborates 3 were synthesized from alkenylsilanes 1 by the reaction with iodosylbenzene and boron trifluoride-diethyl ether or triethyloxonium tetrafluoroborate.The reaction proceeds stereospecifically with retention of configuration of 1.X-ray diffraction analysis of (4-tert-butylcyclohexenyl)phenyliodonium tetrafluoroborate (3b) revealed the highly ionic structure with the distorted T-shape arrangement.Iodonium salts 3 behave like the highly activated species of vinyl iodides due to the high leaving ability of the iodine(III) substituents.Thus, a variety of substituted olefins including α-cyano and α-nitro olefins, vinyl sulfides, vinyl halides and α,β-unsaturated esters, were synthesized from 3 under mild conditions.A ligand coupling mechanism via the formation of 10-I-3 intermediate 27 containing a copper(III) ligand is proposed for the substitutions of 3 with nucleophiles.
- Ochiai, Masahito,Sumi, Kenzo,Takaoka, Yoshikazu,Kunishima, Munetaka,Nagao, Yoshimitsu,et al.
-
p. 4095 - 4112
(2007/10/02)
-
- PALLADIUM-CATALYZED CROSS-COUPLING REACTIONS OF B-ALKYL-9-BBN OF TRIALKYLBORANES WITH ARYL AND 1-ALKENYL HALIDES
-
The reactions of trialkylboranes or B-alkyl-9-BBN with aryl and 1-alkenyl halides take place readily in the presence of PdCl2(dppf) and sodium hydroxide or methoxide to afford alkylatad arenes and alkenes in excellent yields.
- Miyaura, Norio,Ishiyama, Tatsuo,Ishikawa, Masako,Suzuki, Akira
-
p. 6369 - 6372
(2007/10/02)
-
- Stereospecific Rearrangement of 2,2-Disubstituted Vinylsilane Epoxides to the Silyl Enol Ethers of 2,2-Disubstituted Aldehydes
-
The Z- and E-2-ethyl-2-methylvinylsilane epoxides (5a) and (5b) rearrange stereospecifically in the presence of boron trifluoride-diethyl ether to the Z- and E-silyl enol ethers, (6a) and (6b), respectively, of 2-methylbutanal.These silyl enol ethers reac
- Fleming, Ian,Newton, Trevor W.
-
p. 119 - 124
(2007/10/02)
-
- Transformation of Carbon-Oxygen into Carbon-Carbon Bonds Mediated by Low-Valent Nickel Species
-
The substitution of alkoxy groups of enol ethers (1-methoxycyclohexenes, 1-methoxy-1-alkenes, and benzofuran) and aryl ethers (methoxynaphthalenes, cresyl methyl ethers, and dimethoxybenzenes) by hydrogen, alkyl groups, and aryl units, through Grignard reactions catalyzed by bis(triphenylphosphine)nickel dichloride or nickel dichloride, is described.The stereochemistry of the new reaction is portrayed, especially in connection with processes involving ring opening of dihydropyrans and dihydrofurans.The reaction has been applied to the synthesis of a termite trail pheromone and the acetate of the Douglas fir beetle aggregation pheromone.
- Wenkert, Ernest,Michelotti, Enrique L.,Swindell, Charles S.,Tingoli, Marco
-
p. 4894 - 4899
(2007/10/02)
-