NiCl(2)(PCy(3))(2) associated with PCy(3) promotes the selective cross-coupling of aryltosylates with arylboronic acids under relatively mild reaction conditions, and a variety of functional groups are tolerated in both arenes. This is one of the simplest and most efficient experimental procedures for the coupling of arylboronic acids with aryl tosylates reported to date. Reaction: see text.

[reaction: see text] A simple and efficient protocol for the preparation of functionalized styrenes is disclosed that employs the palladium-catalyzed cross-coupling reaction of arylboronic acids with vinyl bromide, generated in situ from 1,2-dibromoethane. The reaction is carried out under mild reaction conditions. Compared with the cross-coupling reactions usually employed to obtain vinylarenes, this protocol is very simple, overcomes the inconvenience of using of ethylene under pressure, and uses air-stable and widely available arylboronic acids instead of vinyl organometallic reagents.

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Reações catalisadas por complexos de metais de transição tais como carbonilação, hidrovinilação e hidrogenação foram empregadas na síntese do ácido α-(3-benzoilfenil)propanóico (Cetoprofeno). Acoplamento do tipo Heck entre 3-bromobenzofenona e etileno conduziu à 3-vinilbenzofenona que na sequência, por carbonilação catalisada por paládio, foi tranformada no α-(3benzoilfenil)propanoato de isopropila com rendimento de 95% e regiosseletividade >99,5%. Hidrólise deste éster conduziu ao Cetoprofeno com 90% de rendimento. Cetoprofeno foi também obtido em duas etapas a partir da 3-vinilbenzofenona via reação de hidrovinilação catalisada por níquel que conduz seletivamente ao 3-(3'-benzoilfenil)-1-buteno (96%), seguido por oxidação desta olefina em ácido. A 3-etenilbenzofenona pôde ser sintetizada a partir da 3-bromobenzofenona via uma reação de acoplamento catalisada por paládio. Este alcino foi carabonilado em presença de paládio conduzindo regiosseletivamente (97%) ao α-(3-benzoilfenil)acrilato de metila. A hidrólise do éster conduz ao ácido α-(3-benzoilfenil)acrílico que foi então hidrogenado enantiosseletivamente ao (S)-Cetoprofeno (95% e.e.) usando um complexo Ru-(S)-BINAP como catalisador. Transition metal-catalyzed reactions including carbonylations, hydrovinylations and hydrogenations have been applied in the synthesis of α-(3-benzoylphenyl)propanoic acid (Ketoprofen). 3-Vinylbenzophenone was obtained from 3-bromobenzophenone by a Pd-catalyzed Heck coupling reaction. Pd-catalyzed carbonylation of this olefin gave the isopropyl α-(3-benzoylphenyl) propionate in high yield (95%) and with high regioselectivity (>99.5%). Ketoprofen was obtained in 90% yield by hydrolysis of the isopropyl ester. It was also obtained in two steps from 3vinylbenzophenone by a Ni-catalyzed hydrovinylation selectively affording 3-(3'-benzoylphenyl)-1-butene, followed by an oxidation. 3-Ethynylbenzophenone was obtained from 3bromobenzophenone by Pd-catalyzed coupling reaction. By means of a Pd-catalyzed carbonylation, this alkyne was converted regioselectively (97%) into methyl α-(3-benzoylphenyl) acrylate (93% yield). Hydrolysis of the ester afforded the α-(3-benzoylphenyl)acrylic acid. Asymmetric hydrogenation of this acid to give (S)-ketoprofen in 95% optical yield was achieved using a chiral Ru-(S)-BINAP catalyst.

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