Diiodoethane, reactions with

Deprotonation readily occurs at C-7, and the resulting anion can further react with various electrophiles. Thus, treatment with BuLi at — 78 °C followed by reaction with diiodoethane was used to prepare the 7-iodo derivatives depicted in Table 2, while the 7-chloro derivatives were prepared by lithiation with lithium diisopropylamide (LDA), followed by reaction with CCI4. The 7-formyl derivative of the parent pyrazolo[l,5- ]pyridine has been prepared in 82% yield by reaction of the BuLi-generated anion with ethyl formate <2001JME2691>. 

Cleavage of lactones and carbonates. Lactones and carbonates react with bromotrimethylsilane to afford bromocarboxylic acid derivatives (equation I) and bromohydrin trimethylsilyl ethers (equation II), respectively acyclic, aliphatic esters do not react with bromotrimethylsilane. lodotrimethylsilane reacts in an analogous fashion with lactones, but in reaction with ethylene carbonate the main product is 1,2-diiodoethane (equation III). The >-bromocarboxylate derivatives are converted into acid chlorides by reaction with SOCL (equation I). 

Other specialized alloys have also been used to prepare skeletal metal catalysts. Raney ruthenium has been prepared from the ruthenium aluminum alloy. 20 A colloidal platinum has been prepared by the action of acetic acid on a platinum lithium alloy. l Skeletal nickel catalysts have been made from a number of intermetallic compounds of nickel with the rare earth elements, lanthanum and samarium. The rare earth element is removed from the alloy by reaction with diiodoethane or dibromoethane which convert the rare earths to the soluble halide salts. 22 Several multicomponent catalysts have also been prepared from the corresponding aluminum alloys. 23-126... 

Preparation. The suitable form of Bal for reaction with allyllithiums is obtained from stirring Ba with 1,2-diiodoethane in ether containing Na2S204. 

Formally analogous to the preceding cases, the preparation of Ybl2 and Smij in tetrahydrofurane was performed by reaction between the metal and 1,2-diiodoethane or diiodomethane at room temperature. Reaction conditions are very mild and yields of the diiodides are quantitative (Namy et al., 1977, 1981). The reaction with 1,2-diiodoethane can be written as follows ... 

Simmons-Smith reaction of cyclohexene with diiodomethane gives a single cyclopropane product, but the analogous reaction of cyclohexene with 1,1-diiodoethane gives (in low yield) a mixture of two isomeric methyl-cyclopropane products. What are the two products, and how do they differ ... 

Pu sulfate complexes for stability constant determination reaction of Pu with diiodoethane. 42-43... 

Reduction of nitroalkanes RNO2 with samarium(II) iodide, obtained from samarium and 1,2-diiodoethane, yields either alkylhydroxylamines RNHOH or alkylamines RNH2, depending on the amount of the reagent434. The base-catalysed reaction of nitroalkanes with phenyl(vinyl) sulphoxide (399) yields the conjugate adducts 400, which fragment to allylic nitro compounds 401 on thermolysis435. 

Solutions of dipositive lanthanide cations have been obtained in liquid ammonia, ethanol, THF, acetonitrile and hexamethylphosphoramide. Ions stabilized, or for which there is evidence for stabilization, include Nd2+, Dy2+ and Tm2+ as well as Eu2+, Yb2+ and Sm2+. The non-hydroxylic solvents are best at stabilizing M2+ ions. Thus NdCl2(THF)2 has been reported from the reduction of NdCl3 in THF by Na(naphthalene),657 and corresponding reductions of MC13 (M = Eu, Yb or Sm) have also been achieved.658 Solutions of solvated MI2 (M = Sm or Yb) in THF may easily be made by the quantitative reaction of the metal with 1,2-diiodoethane, producing ethane. The solid THF adducts may be isolated.659... 

In recent years, exposing the preparation of the reagent from samarium metal and an oxidant to different stimuli has led to significant improvements in reaction time. Concellon utilized the sonication of samarium metal and iodoform at room temperature to give a solution of Sml2 in THF in approximately 5 min (Scheme 2.3).5 This approach was also used by Flowers to synthesise other Sm(II) species.6 It was also reported that using different oxidants, such as 1,2-diiodoethane, diiodomethane and iodine, works just as well with this technique.5... 

Focus on the stereochemistry of the three-membered ring. Simmons-Smith reaction of 1,1-diiodoethane with the double bond occurs with syn stereochemistry and can produce two isomers. In one of these isomers (A), the methyl group is on the same side of the three-membered ring as the cyclohexane ring carbons. In B, the methyl group is on the side of the three-membered ring opposite to the cyclohexane ring carbons. 

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