Phenyllithium bromide

The addition of phenyllithium to 6-arylpyridazin-3(2Er)-one takes place at position 6 to give 6-aryl-3-oxo-6-phenyl-l,2,3,4-tetrahydropyridazine and the reaction of 6-aryl-2,4-diphenylpyridazin-3(2H)-one with phenyllithium or phenylmagnesium bromide affords 6-aryl-2,3,4,6-pentaphenyl-l,2,3,4-tetrahydropyridazine (80S457). 

Aryl-2-phenyl-4,5-dihydropyridazin-3(2//)-ones react either with phenylmagnesium bromide or with phenyllithium to give 6-aryl-2,6-diphenyl-l,4,5,6-tetrahydropyridazin-3(2//)-ones (135) (products of 1,2-addition to the azomethine bond), while 2-methyl-6-phenyl-4,5-dihydropyridazine-3(2//)-one reacts with two equivalents of phenylmagnesium bromide at the carbonyl and azomethine group to produce 2-methyl-3,3,6,6-tetraphenyl-hexahydropyridazine (136) (Scheme 53) (80JPR617). 

An aryl methanesulfonate was cleaved to a phenol by phenyllithium or phen-ylmagnesium bromide it was reduced to an aromatic hydrocarbon by sodium in liquid ammonia. ... 

The 16a,l7a-epoxide (12) can be made to react with methylmagnesium bromide or methyllithium as well as phenyllithium to yield (13a) and (13b), respectively, after ketal cleavage. 

In addition, there is a cleavage reaction whereby a perfluoroorgamc group is cleaved from a metal by a base, for example, phenyllithium [4], ethylmagnesium bromide [5], or a fluoride ion [6] (equations 3-5)... 

The first clearly authenticated preparation of an isoindole was reported by Wittig et in 1951. It was found that elimination from isoindolinium bromides and iodides with bases such as aryl- and alkyllithium afforded 2-substituted isoindoles in variable yields. For instance, 2,2-dimethylisoindolinium bromide (5) on treatment with one equivalent of phenyllithium in ether under nitrogen, evolved methane and gave 2-mcthylisoindole (6) in 74% yield. With methyl-lithium as base, a slightly lower yield was obtained. 

Di-o-xylyleneammonium bromide (7) gave only an 8% yield of 2-o-tolylisoindole (8) with phenyllithium, although the yield was... 

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... 

No difference in diastereoselectivity was observed when phenyllithium and phenylmagnesium bromide were added to tetrahydrofurfural (15, R = H) in both cases there was a moderate preference for the chelation-controlled reaction product. The same trend holds for tetrahydro-5,5-dimethylfurfural (15, R = CH3), however, with a lower level of stereoselectivity58. 

The lower diastereoselectivity found with aldehyde 15 (R = CH3) can be explained by the steric influence of the two methyl substituents in close vicinity to the stereogenic center, which probably diminishes the ability of the ether oxygen to coordinate. In contrast, a significant difference in the diastereoselectivity was found in the additions of phenyllithium and phenylmagnesium bromide to isopropylidene glyceraldehyde (17)58 (see also Section 1.3.1.3.6.). Presumably the diastereo-sclcctivity of the phenyllithium addition is determined by the ratio of chelation-controlled to nonchelation-controlled attack of the nucleophile, whereas in the case of phenylmagnesium bromide additional chelation with the / -ether oxygen may occur. Formation of the -chelate 19 stabilizes the Felkin-Anh transition state and therefore increases the proportion of the anZz -diastereomeric addition product. 

Allylmagnesium bromide, 41, 49 reaction with acrolein, 41, 49 5-Allyl-l,2,3,4,5-pentachlorocyclopen-tadiene, 43, 92 Allyltriphenyltin, 41, 31 reaction with phenyllithium, 41, 30 Aluminum chloride, as catalyst, for isomerization, 42, 9 for nuclear bromination and chlorination of aromatic aldehydes and ketones, 40, 9 as Friedel-Crafts catalyst, 41, 1 Amidation, of aniline with maleic anhydride, 41, 93... 

Phenyl isocyanate, conversion to di-phenylcarbodiimide, 43,31 Phenyl isocyanide, 41,103 Phenyllithium, reaction with allyltri-phenyltin, 41, 30 standardization of, 41, 32 Phenylmagnesium bromide, 41, 91 reaction with ( r(-butyl perbenzoate, 41,91... 

So far, only cuprates with a 1 1 copper/lithium ratio have been considered. Treatment of phenyllithium with various substoichiometric quantities of copper bromide in DMS as solvent afforded so-called higher order cuprates, of which two were characterizable by X-ray crystallography. These have the overall stoichiometries Cu2Li3Ph5(DMS)4 and Cu4Li5Ph9(DMS)4 [114, 115). The structure of the former compound in the solid state is shown in Fig. 1.26. 

When cyclohexanone oxime 6e was used as amination reagent, primary amines were obtained from phenylmagnesium bromide. Reaction of 6e with alkyl Grignard reagents gave aziridines, whereas reaction with phenyllithium gave aziridine and the addition product of phenyllithium to the imine (Scheme 57) 24. 

A new synthesis of dibenzo[a,g]quinolizinium derivatives also makes use of an aldehyde cyclization (Scheme 80) (75JAP(K)7596599). In one example, a benzyl bromide bearing an acetal-masked aldehyde group in the ortho position (126) was allowed to react with the anion (127) generated by the action of phenyllithium on a Reissert compound. The condensation product was heated with alkali to cleave the benzoyl and cyano groups to yield the isoquinoline (128), then the acetal was cleaved and the resulting aldehyde cyclized to (129), presumably under acid conditions. 

Verwcndet man in der 3. Stufe des angegebenen Formelschemas einen Aldehyd anstelle des Alkyl-bromids, so erhalt man einen jS-Amino-alkohol, z. B. durch Metallierung von (2-Anilino-ethyl)-quecksilber-bromid (aus Ethen durch Aminomercurierung) mit Phenyllithium und anschlicBende Umsetzung mit 2-Methyl-propanal l-Anilino-3-hydroxy-4-methyl-pentan (70%)2. 

To the three-necked flask equipped as above and containing 0.42 mole of A-methyl-A-phenyllithium aminoacetylide is added dropwise 88 gm (0.65 mole) of n-butyl bromide in 160 ml of hexamethylphosphoramide. The reaction is exothermic and the ether refluxes. At the end of the addition the ether is removed by distillation and the temperature is raised and kept at 75°C for 2 hr or until the absorption band at 2050 cm-1 disappears. The product is obtained by distilling it directly from the reaction medium under reduced pressure to afford 58 gm (75%), b.p. 88°C (0.1 mm), n 1.5464. 

Metalation. Benzene reacts with alkali metal derivatives such as methyl or ethyUithium in hydrocarbon solvents to produce phenyllithium [591-51-5], C6H5Li, and methane or ethane. Chloro-, bromo-, or iodobenzene will react with magnesium metal in ethereal solvents to produce phenylmagnesium chloride [100-59-4], C6H5MgCl, bromide, or iodide (Grignard reagents) (32). 

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