Lithium metal reactions with

For over 15 years we have conducted research utilizing metal atoms in low temperature spectroscopic and synthetic studies at Rice University.8 Our synthetic work was started in the late 1960s with the work of Krishnan, on lithium atom reactions with carbon monoxide, extended by Meier- in his studies of lithium atom reactions with water and ammonia and expanded over the next several years to include metal atom interactions with HF, H2O, H3N, H4C, and their hundreds of organic analogs—RF, R2O, ROH, R3N,. . . H3N, R4C, R3CH, etc. A most exciting aspect of... 

Due to the high interest in metalation reactions with lithium amide or alkyllithiums, an indicator scale of lithium ion pairs in THF has been developed119. Aggregation studies have indicated that organolithium species exist predominantly, if not exclusively, as monomers in the 10-3-10-4 M concentration range. Particular attention has been devoted to the lithium and caesium ion-pair acidities of diphenylamine in THF120 that, at 25 °C, have been found to be 19.05 and 24.20, respectively. 

Both 1 and 2 are stereochemically stable and shelf stable -metalated ethers. Subsequent tin-lithium exchange reaction with bulyllithium occurs as expected with retention of configuration in both cases51. 

Furans in general can be attacked by nucleophiles, if they are substituted with electron-withdrawing groups (exceptions are the metalation reactions with butyl lithium, etc.). It is possible to cleave 2-nitrofuran with sodium methoxide in methanol, and the reaction yields fumaric acid monoester and methyl-imws-3-formylacrylate304 ... 

Alkali-metal tetrahydraborate reduction of phosphorus halides is of limited utility . Lithium tetrahydroborate reaction with PClj or PClj in Et20 at — 80°C produces PHj, but yields are low" ... 

Metallation of certain reactive hydrocarbons provides yet another route to several otherwise difficultly accessible lithium derivatives.59 Thus when a hydrogen atom on carbon has aryl or vinyl groups as neighbors it may be replaced by lithium under the action of organolithium compounds. Further, an 0-hydrogen atom of, inter alia, aryl ethers and sulfides can be replaced by lithium in reactions with butyllithium or phenyllithium.60... 

Azines and diazines are capable of preparatively useful metalation reactions with lithium organyls [180]. 

A particularly interesting mixed-metal polymer was synthesized from the metallocene 19. This reaction (Scheme XV) was conducted by first converting the phenol functionalities of 19 to lithium phenoxides via reaction with methyl lithium. Subsequent reaction with (ri -C5H5)2ZrCl2 gave the desired polymeric product. Detailed studies of the physical and chemical properties of this polymer are currently in progress. 

Lithium/hexamethylphosphoramide Reactions with alkali metals in hexamethylphosphoramide Reductive N-alkylation of azo compounds... 

Polymers prepared by the above procedure have molecular weights up to 80,000. It is also possible to start with diphenoxysiloxane and catalyze the reaction with sodium or lithium metals. Reactions of cyclic silazanes with arylene disalanols yield polymers with molecular weights as high as 900,000 ... 

A redox cyclopentadienyl iron moiety can also be introduced into the poly(vinyl chloride) backbone by a similar technique.Many other attempts were reported at replacing the halogens of poly(vinyl chloride), poly(vinyl bromide), and poly(vinyl iodide) with an alkali metal or with a hydrogen. For instance, in an effort to form poly(vinyl lithium), the polymers were reacted with organolithium compounds and with metallic lithium. The reactions with alkyllithium, however, resulted in substitutions by the alkyl groups, similarly to the reactions shown previously ... 

To determine whether the species introduced on doping carry spin, in situ ESR measurements were conducted during doping in parallel with optical measurements. The P3MT film sample (approximately 2 jj.m in thickness) on the ITO substrate was mounted in electrochemical cells as described by Chen et al. [233,236]. The P3MT sample, electrolytic solution, and counter electrode (lithium metal) sandwiched with nickel mesh (which is inert to the electrochemical reaction) were assembled in an inert atmosphere inside an ESR quartz tube. To avoid having the lithium metal and nickel mesh inside the ESR apparatus cavity, the... 

The coupling of alkynyl metals with tertiary alkyl halides without the occurrence of elimination or other side-reactions has been achieved with the organo-alanes, which are prepared from the alkynyl-lithium by reaction with anhydrous AlCl3. Thus, reaction of (Bu C3C— )3A1 with 1-bromoadamantane gave (735 96%) two of the three acetylene units are not utilized and can be recovered nearly quantitatively. It appears that starting material savings caimot be made by using alkynyldialkylalanes since elimination processes tend to occur with t-alkyl halides. The reaction mechanism is not clear. 

---