Lithium phenyl

If preferred, the apparatiaa depicted in Fig. II, 7, 13 may be used. This enables an oxygen-free nitrogen atmosphere to be maintained in the apparatus and leads to the best yield of phenyl-lithium. 

Dibenzo[6,e]borinate, 5-aryl, 1, 642 Dibenzo[b,e]borinate, 5-mesityl-synthesis, 1, 643 Dibenzo[b,e]borinate, 5-phenyl-lithium salt... 

The reactivity of the 1-methyl group and of corresponding positions (i.e., a-carbon atoms) in other l-alkyl-j8-carbolines, analogous to that in a-picoline, quinaldine, and isoquinaldine, is due to the acidity of this center. Deprotonation yields a resonance-stabilized anion (288) which reacts readily with electrophilic reagents. Metallation with phenyl-lithium of the 1-methyl group of a l-methyl-j8-carboline derivative in which the indole nitrogen is protected, first described by Woodward... 

Both 1- (5) and 2-fluoronaphthalene (9) yield with phenyl-lithium the same (Mymmetrical aryne (6) after subsequent carbona-tion, mixtures containing l-phenylnaphthalene-2-carboxylic acid (7) and 2-phenylnaphthalene-l-carboxylic acid (8) in the ratio 1 1.7 were... 

The solution of phenyl-lithium is cooled to -20°C and to this a solution of 12.7 grams of 1,3-dimethyl-4-piperidone, prepared according to the method of Howton, J. Org. Chem. 

On the other hand, -chelation does not seem to play a role with the open-chained dibenzyl-protected glyceraldehyde 20 since there was no difference in the diastereoselcctivity of phenyl-lithium and phenylmagncsium bromide addition58. 

The addition to 2-cyclohexcnone or (fj-d-phenyl-S-penten -one gave products with d.r. 99 1. Since the configuration of 5 was not determined, a detailed interpretation of the stereoselectivity is not possible. The 1,4 addition of the chiral cuprate reagent, lithium [2-(l-dimethylamino-ethyl)phenyl](2-thienyl)cuprate, to ( )-2,2-dimethyT5-phenyl-4-penten-3-one produced predominantly one diastereomer with d.r. 99 1, while the 1,4-addition of [2-(l-dimethylaminoethyl)-phenyl]lithium to the same enone gave predominantly the opposite diastereomer (d.r. 3 97). 

Aus Fluor-halogen-olefinen werden dagegen wegen der mit Fluor leicht ablaufenden nucleophilen Substitutionsreaktionen Substitutionsprodukte (z. B. Tolan mit Phenyl-lithium aus Trifluor-brom-athylen oder l,2-Difluor-l,2-dichlor-athylen) erhalten (s. ds. Handb., Bd. V/2a, S. 42ff.). 

This type of metallic exchange is used much less often than 12-32 and 12-33. It is an equilibrium reaction and is useful only if the equilibrium lies in the desired direction. Usually the goal is to prepare a lithium compound that is not prepared easily in other ways, for example, a vinylic or an allylic lithium, most commonly from an organotin substrate. Examples are the preparation of vinyllithium from phenyl-lithium and tetravinyltin and the formation of a-dialkylamino organolithium compounds from the corresponding organotin compounds ... 

Allcock HR and Chu CTW, Reaction of phenyl lithium withpolydichlorophosphazene. Macromolecules, 1979, 12, 551-555. 

The phosphonium salt (116) gave the phosphorane (117) with phenyl-lithium although it has hydrogen atoms attached to carbon bonded to phosphorus. ... 

The cage-like phosphonium salt (17) with phenyl-lithium in THF gave the phosphorane (18) which probably owes its great stability to the relief of strain in the ring structure on changing the bond angle at phosphorus to 90°. For the photolysis of (18) see Chapter 10, Section 1. 

The quality of phenyl-lithium used to generate ylides can have a pronounced effect on the stereochemistry of olefin synthesis. In the reactions of the ylide (36) with the aldehydes (37) c/5-olefins were obtained using a phenyl-lithium solution containing one equivalent of total base while /m/ij-olefins resulted from the use of an amount of this solution containing one equivalent of genuine phenyl-lithium together with six equivalents of other, unspecified, base. ... 

Bromobenzene was added to lithium in an ethereal medium to obtain phenyl-lithium. 

A modification to method C devised by Jake Cha has enabled the synthesis of 2-substituted benzodihydrofurans, while in route to phenolic constituents from Dalbergia cochinchinensis such as 49.26 For example, addition of phenyl lithium to 2-OBoc-4,5-bis-methoxybenzaldehyde 47 followed by the addition of iodomethyl Grignard proceeds to the benzodihydrofuran 48 in a 60% yield (Fig. 4.25). 

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