Murahashi coupling

Table 8 Kumada-Murahashi couplings of primary alkyl chlorides with aryl Grignard reagents...

Nagaki A, Kemnoku A, Moriwaki Y et al (2010) Cross-coupling in a flow microreactor. Space integration of lithiation and Murahashi coupling. Angew Chem Int Ed 49 7543-7547... 

The MCPT research group and the University of Kyoto investigated the Murahashi coupling in a flow microreactor system [76] (Figure 11.27). Integration with the... 

F. 9.6 Space integration of Br-Ii exchange of p-methoxybromobenzene and Murahashi coupling with bromobenzene... 

After Kumada and Tamao and Corriu independently reported the nickel(II) salts-and complexes-catalyzed cross-coupling reaction of Grignard reagents with aryl and alkenyl halides, the Pd-catalyzed reaction of Grignard reagents was first reported by Murahashi. ... 

The formal coupling of two alkylidyne units had previously been achieved by Murahashi et al. in the reaction shown in Eq. (176) (183). Pyrolysis or photolysis of the bis(oi-diazobenzyl) palladium complex 226 was found to result in formation of diphenylacetylene and a minor amount... 

Murahashi, S.-l. Palladium-catalyzed cross-coupling reaction of organic halides with Grignard reagents, organolithium compounds and heteroatom nucleophiles. J. Organomet. Chem. 2002, 653, 27-33. 

Kumada-Murahashi cross-couplings of primary alkyl bromides and tos-ylates have been described by Kambe [34]. Pd(acac)2/butadiene was employed as the catalyst, and couplings of alkyl and aryl Grignard reagents were achieved. The reactions proceed in the presence of an aryl chloride, an aryl bromide, and a styrenyl group. A typical cross-coupling is illustrated in Eq. 13. 

Suzuki-Miyaura reaction (a) Suzuki A (1998) In Diederich F.Stang PJ (eds) Metal-catalyzed cross-coupling reactions. WUey-VCH,Weinheim,pp 49-97 and references therein Kumada reaction (b) Yamamura M,Moritani I, Murahashi S (1975) J Organomet Chem 91 C39 (c) Tamao K, Kiso Y, Sumitani K, Kumada, M (1972) J Am Chem Soc 94 9268 ... 

Vinyl snlfides are valnable synthetic intermediates. Several examples of crosscoupling reactions between vinyl halides and sulfur nucleophiles have been reported. Beletskaya reported the stereospecific coupling of distannylsulfides with vinyl halides, while Murahashi reported a similar reaction but using alkali thiolates (Eq. 11). /3-Bromostyrene was converted to (2-phenyl-ethenylthio) benzene in >95% yields and... 

In 1975, both Cassar [72] and Murahashi and coworkers [73] reported on the applications of palladium complexes to catalytic cross-coupling chemistry [74]. Initially, Cassar compared nickel and palladium complexes in the catalytic crosscoupling between aryl or alkenyl halides and terminal alkynes, and found that nickel-based compounds exhibited no catalytic activity. In contrast, [Pd(PPh3)4] enabled catalytic coupling reactions of various organic halides bearing C(sp )-X bonds as reactive functional groups, notably in the absence of any copper [75] additives (Scheme 1.20) [72]. 

Scheme 1.23 Palladium-catalyzed cross-coupling of Crignard reagent 56 (Murahashi, 1975).

Also in 1975, Murahashi probed the use of palladium catalysts in crossmagnesium-based nucleophiles. While stoichiometric amounts of [Pd(PPh3)4] were required for reactions with lithium derivatives as nucleophiles [79], the corresponding Grignard [80] reagents could be coupled with catalytic amounts of palladium complexes (Scheme 1.23) [73, 74]. 

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