- Cycloneophylpalladium(IV) Complexes: Formation by Oxidative Addition and Selectivity of Their Reductive Elimination Reactions
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The cycloneophylpalladium(II) complexes [Pd(CH2CMe2C6H4)(κ2-N,N′-L)] (L = RO(CH2)3N(CH2-2-C5H4N)2, R = H, Me) undergo oxidation to Pd(IV) with bromine or iodine to give [PdX(CH2CMe2C6H4)(κ3-N,N′,N″-L)]X (X = Br, I) or with methyl iodide to give the transient complexes [PdMe(CH2CMe2C6H4)(κ3-N,N′,N″-L)]I. The products of Br2 and I2 oxidation, [PdX(CH2CMe2C6H4)(κ3-N,N′,N″-L)]X (X = Br, I), are sufficiently stable to be isolated, but they decompose slowly in solution by reductive elimination to give the palladium(II) products [PdX(κ3-N,N′,N″-L)]X (X = Br, I). The organic products are formed via either CH2-Ar or CH2-X bond formation. In the latter case, neophyl rearrangement and protonolysis steps follow reductive elimination to give a mixture of organic products. The methylpalladium(IV) complexes [PdMe(CH2CMe2C6H4)(κ3-N,N′,N″-L)]I decompose at 0 °C by selective reductive elimination with Me-Ar bond coupling to give the alkylpalladium(II) complex [Pd(CH2CMe2-2-C6H4Me)(κ3-N,N′,N″-L)]I. The mechanisms of the reactions have been explored by kinetic studies.
- Behnia, Ava,Blacquiere, Johanna M.,Fard, Mahmood A.,Puddephatt, Richard J.
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- PROCESS FOR THE PREPARATION OF N-IODOAMIDES
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The present invention provides new stable crystalline N-iodoamides - 1-iodo- 3,5,5-trimethylhydantoin (1-ITMH) and 3-iodo-4,4-dimethyl-2-oxazolidinone (IDMO). The present invention further provides a process for the preparation of organic iodides using N-iodoamides of this invention and recovery of the amide co-products from waste water.
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Paragraph 00291-00292
(2015/05/26)
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- Oxidative cross-coupling through double transmetallation: Surprisingly high selectivity for palladium-catalyzed cross-coupling of alkylzinc and alkynylstannanes
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Two different organometallic reagents now can cross-couple together with the oxidative cross-coupling strategy. Palladium catalyzed oxidative cross-couplings of alkylzinc and alkynylstannane reagents using desyl chloride as the oxidant have been explored, which produce the desired Csp-Csp3 cross-coupling product in surprisingly high selectivity and yields. The current catalytic system tolerates the presence of β-H, and the reactions using long chain alkyl zinc reagents gave the cross-coupling product in excellent yields and selectivities. Copyright
- Zhao, Yingsheng,Wang, Haibo,Hou, Xiaohui,Hu, Yanhe,Lei, Aiwen,Zhang, Heng,Zhu, Lizheng
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p. 15048 - 15049
(2007/10/03)
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- Mechanistic study of the reaction of 1,1-dihalo-2-methyl-2-phenylpropanes with LDA. Evidence for radical and carbene pathways
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An attempt was made to determine the mechanisms involved in the reactions of the model systems 1,1-dichloro-2-methyl-2-phenylpropane (1) and 1,1-diiodo-2-methyl-2-phenylpropane (2) with LDA.These systems were chosen as ones capable of providing evidence for the formation of radical as well as carbene products.The techniques employed in investigating the mechanistic features of these reactions involved studying the effect of the leaving group, the effect of radical and carbene trapping agents on the product distribution, and isotopic tracer experiments using labeled solvent (THF-d8) and nucleophile (LDA-d2).The major product of the reaction of the geminal dichloride (1) is thought to be derived from a chlorocarbene, whereas the geminal diiodide (2) appears to form products derived from both carbene and radical intermediates.On the basis of the results of radical trapping experiments and those of deuterium-labeling experiments, evidence is presented to support the notion that products A, E, and H are derived from a radical precursor.In addition, products A and H are also believed to be formed from the vinilyc halide D (or B) and the monoiodide E, respectively.Reasonable mechanisms for the formation of the other products formed in these reactions have been proposed on the basis of the available data.
- Ashby, E. C.,Mehdizadeh, Ali,Deshpande, Abhay K.
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p. 1322 - 1330
(2007/10/03)
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