Aryl with aryllithiums

Alteration of the relative reactivity of the ring-positions of quinoline is expected and observed when cyclic transition states can intervene. Quinoline plus phenylmagnesium bromide (Et20,150°, 3 hr) produces the 2-phenyl derivative (66% yield) phenyllithium gives predominantly the same product along with a little of the 4-phenylation product. Reaction of butyllithium (Et 0, —35°, 15 min) forms 2-butylquinoline directly in 94% yield. 2-Aryl- or 6-methoxy-quinolines give addition at the 2-position with aryllithium re-agents, and reaction there is so favored that appreciable substitution (35%) takes place at the 2-position even in the 4-chloroquinoline 414. Hydride reduction at the 2-position of quinoline predominates. Reaction of amide ion at the 2-position via a cyclic... 

Reactions of organoboron polymer electrolytes with aryllithium reagents suffered low conversion due to relatively low reactivity of the mesitylborane unit. Moreover, incorporation of aryl substituent in side chains resulted in higher glass-polymer electrolyte-transition temperatures. 

Treatment, at low temperature, of either 229 with lithium pyrrolidinide, or 230 with aryllithium, and subsequent alkylation with methyl iodide allowed the isolation of 6-methylsulfanyl-5-aryl-2,3-dihydropyrrolizines 231 in moderate to good yields <2000JOC3341 A possible mechanism was postulated as shown in Scheme 58. 

Reaction of 4,7-phenanthroline with aryllithiums gives the 3-aryl- and 3,8-diaryl-4,7-phenanthrolines.72,284 The dihydro intermediates were isolated. 

A 1 1 mixture of (E)- and (Z)-allyloxysilanes 231 was prepared by the reactions of ( )-trimethylsilylvinyl sulfone 229 with aryllithiums followed by the addition of aliphatic aldehydes and cyclohexanone (equation 147). An anionic 1,4-silyl migration from C to O in the lithium alkoxide 230 was proposed to be involved. On the other hand, lithium alkoxide 232 lacking an aryl group was stable and gave no rearranged product even at room temperature (equation 148)360. 

Asymmetric arylation of chiral oxazolines has provided a versatile method for the arylation of enoates. For example, 104 was arylated with an aryllithium re-... 

Aryl thiols. Aryllithiums react with this disulfide to form crystalline dithiocarbam-ates, which are cleaved to aryl thiols on alkaline hydrolysis (equation 1). 

CO, BuaSnH, and NCCMe2N=NCMe2CN (AIBN). Aryl ketones can be prepared from aryltrimethylsilanes ArSiMea and acyl chlorides in the presence of AlCla Aryllithium and Grignard reagents react with iron pentacarbonyl to give aldehydes ArCHO. The reaction of CO with aryllithium may occur by electron transfer. ... 

The traceless anchors based on silicon just described are limited by the need to synthesize a preformed handle consisting of the first building block and the silicon linker. Moreover, traceless release from conventional aryldialkylsilanes is complicated by their low hydrolytic stability and loss of silicon from the resin in the cleavage process. The silyl chloride resin 8h can be used to anchor aryl rings by reaction with aryllithium reagents. The anchor is stable to concentrated TFA and bases, but treatment with TBAF cleaves the final products [353]. 

The well established alkylation of phosphorylated benzyl carbanions has been complemented by the arylation of purely alkyl species. Thus, diethyl (chloromethyl)phosphonate reacts with aryllithium reagents to give the diethyl esters of benzylic phosphonic acids The alternative procedure has been adopted in a synthetic route to isoprenyl (phos-phinylmethyl)phosphonates. Here, a lithiated dialkyl alkylphosphonate is acylated using an ester of the phosphonochloridic acid, R P(0)(0H)C1, where R is an isoprenoid residue. The acylation process has also been carried to with (R0)2P(0)C1 or (Me2N)2P(0)Cl ... 

A similar approach to aryl- and heteroaryl(phenyl)iodonium triflates 285 involves the ligand-transfer reaction between vinyliodonium salt 284 with aryllithiums (Scheme 2.83) [405]. Likewise, the reaction of ( )-[(3-(trifluoromethanesulfonyloxy)ethenyl](aryl)iodonium triflates 286 with aryllithiums or alkynyllithiums can be used for a selective preparation of the respective diaryl- or alkynyl(aryl)iodonium triflates in high yields [406]. 

XXXXII. The latter is cyclized to oxazoline XXXXIII by treatment with thionyl chloride. Oxazoline XXXXIII reacts with aryllithium or aryl Grignard reagent to produce the ort/zo-arylated oxazoline XXXXIV. This is further hydrolyzed with acid to the respective biphenic acid XXXXV [39,40], Scheme 18. 

Amination. Trimethylsilylmethyl azide reacts with aryl Grignard reagents at room terr ierature to give aniline derivatives in 70-95% yield (eq 1). An intermediate of the reaction is probably a triazene, which is hydrolyzed by neutral water to yield an amine. Amination of Grignard reagent with other azides (sulfonyl azide and thiomethyl azide) is known, but relatively drastic conditions are required to decompose the intermediate. The azide also reacts with aryllithium compounds to afford amines (eq 2), but yields are generally lower. ... 

Formation of aryl Grignard reagents (Section 14 4) Aryl halides react with magnesium to form the corresponding arylmagnesium halide Aryl iodides are the most reac tive aryl fluorides the least A similar reaction occurs with lithium to give aryllithium reagents (Section 14 3)... 

For the synthesis of a suitable arylboron compound, usually an aryl halide is converted to an aryllithium or aryl Grignard derivative, and then reacted with a trialkoxyborane to yield an arylboronic ester, e.g. the phenylboronic acid diisopropyl ester 13 from bromobenzene 11 ... 

The alkylation of heterocyclic nitrogen compounds with alkyllithium reagents is called Ziegler alkylation. Aryllithium reagents give arylation. The reaction occurs... 

Arylcopper intermediates can be generated from organolithium compounds, as in the preparation of cuprates.95 These compounds react with a second aryl halide to provide unsymmetrical biaryls in a reaction that is essentially a variant of the cuprate alkylation process discussed on p. 680. An alternative procedure involves generation of a mixed diarylcyanocuprate by sequential addition of two different aryllithium reagents to CuCN, which then undergo decomposition to biaryls on exposure to oxygen.96 The second addition must be carried out at very low temperature to prevent equilibration with the symmetrical diarylcyanocuprates. 

The aryl bromides undergo facile metalation with butyl lithium to produce aryllithium derivatives with the expected organometallic activity.9 For example, reaction of lithiated PPO with carbon dioxide produces a carboxylated PPO which exhibits unique blending characteristics18. 

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