Aryl halides coupling reaction with

Biphenyl bond formation has been achieved in the diiodobiaryl derivative 41 by an intramolecular aryl halide coupling reaction promoted by tetrakis(tri-phenylphosphine) nickel. This short and efficient route gave the dibenzazonine 42 in good yield (42) (Scheme 9). In a similar way, tetrasubstituted derivative 43 was successfully coupled with the more easily prepared tris(triphenylphos-phine)nickel, giving 44 in 62% yield. Subsequent debenzylation led to the most efficient synthesis of dibenzazonine 35a reported to date (43). 

In comparison to the nickel-catalysed aryl halide coupling reactions, the palladium-catalysed analogues are not sensitive to the steric hindrances and to the presence of nitro group. The nickel(O) complexes are more reactive than the appropriate palladiums, and thus more effective in the reactions with the least reactive aryl chlorides. However, the palladium complexes are more convenient and selective, even in the cross-coupling reaction of two electronically different aryl halides. 

The copper species formed depends on the solvent, and three different species were detected by F NMR, although the structure of each species was not elucidated [245 This copper reagent undergoes a variety of coupling reactions with aryl, alkenyl, allyl, and acetylenic halides [244, 245 (equation 162)... 

In a related reaction, aryl halides couple with vinyl tin reagents to form styrene derivatives in the presence of a nickel catalyst, for example, ... 

Suzuki coupling reactions with aryl halides. Two as-prepared BaCei cPd c03. ( materials (x = 0.05 and 0.10) were successfully utihzed in several Suzuki coupling reactions. Both aryl iodides and aryl bromides react smoothly with 4-phenylboronic acid, eq 1, to yield the corresponding biatyls in high yields (> 95%). For both 4-bromoanisole and 4-iodoanisole, the biatyl yields reached nearly 100% in 3 min with BaCeo 95Pdoo503 5 as the catalyst, corresponding to an effective TON of ca. 2,000 and an effective TOF of nearly 50,000 h. Resnlts are smmnarized in Table 27.1. 

Coupling of organostannanes with halides in a carbon monoxide atmosphere leads to ketones by incorporation of a carbonylation step.249 The catalytic cycle is similar to that involved in the coupling of alkyl or aryl halides. These reactions involve Reactions involving a migration of one of the organic substituents to the carbonyl carbon, followed by... 

Intramolecularly coordinated A1 and In compounds (e.g., (75), (76)) transfer the Me group in cross-coupling reactions with various aryl halides, including chlorides, catalyzed by Pd and Ni complexes.16 262 265 Monoorganobismuth compounds are reactive in cross-coupling reactions only if they contain an intramolecularly coordinating residue (77),266 267... 

Although not directly analogous to the coupling of thiols with aryl halides, the reaction of thiourea with an aryl halide in the presence of palladium catalyst, nevertheless, can be used to generate a thiophenol from an aryl halide after hydrolysis (Equation (39)).129 This process occurred in greater than 90% yield with a variety of simple aryl halides ... 

Alkynyltin compounds also take part in Stille coupling reactions with alkyl, aryl, or acyl halides or triflates (e.g., Equation (89)).251 These reactions are covered in Volume 11. 

A recent report has shown that tricyclopropylbismuth can be utilized in the cross-coupling reaction with aryl halides and triflates [57]. Representative examples are shown in Scheme 38. Addition of a base activator and excess of the bismuth reagents are necessary to obtain the coupling products in good yields, although more than one cyclopropyl group was transferred when 0.5 equivalents of... 

The added advantage of the C (1 )-stannylated glycals is their abUity to participate in palladium-catalyzed coupling reactions with organic halides, a process independently reported by Beau [75] and Friesen [81]. Vinyl stannane 237 can be benzylated, allylated or acylated provided that appropriate catalysts are used [75,77] and representative examples are given in Scheme 59. The C-arylation of... 

The alkenylmagnesium species generated by the Fe-catalyzed arylmagnesiation can be trapped by electrophiles. For example, the cross-coupling reaction of the alkenyhnagne-sium species with an aryl halide is achieved with a nickel catalyst, giving a tetrasubstituted olefin 21 in good overall yield (Scheme 17). ... 

Organozinc reagents, including the Reformatsky reagents, are extensively used in transition metal catalysed coupling reactions with aryl halides or triflates, vinyl halides, and allylic halides or acetates, as reviewed by Erdik156. Nickel and palladium complexes are... 

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