Tandem carbonylation-arylation

A similar substituted furan synthesis was realized via a Pd-catalyzed tandem carbonylation-arylation using an a,p-acetylenic ketone, carbon monoxide, and bromothiophene [104],... 

RXN21 Tandem Carbonylation-Arylation with Alkynes 120... 

RXN67 Intermolecular Tandem Carbonylation-Coupling-Cyclization Process of Aryl Halides with Terminal Alkynes... 

RXN78 Tandem Carbonylation-Cyclization of (Z)- p-lodoenones and Related Reaction from Aryl Iodides and Internal Alkynes... 

Recently, ruthenium porphyrins have been used as catalysts for tandem carbonyl yhde formation/cycloaddition transformation [200,201]. The dia-stereoselectivity of the reaction with a variety of alkyl- and aryl-substituted a-diazo ketones was found to be highly substrate-dependant. Finally, highly selective intra- and intermolecular couphng reactions of diazocompounds to form cis-alkenes, including organic macrocychc compounds were developed by Che et al. [202]. 

Also exploiting an intramolecular C—S bond formation, Bryan et al. extended their investigation of gem-dihalovinylarene substrates in the synthesis of heterocycles to encompass a thiol analogue (Scheme 34.38, disconnection D-2). The combination of an unusual palladium-catalyzed S-alkenylation with a second cross-coupling process, such as a Suzuki, Heck, or Sonogashira reaction led to diversely functionalized benzothiophenes such as 67, produced in excellent yield (Scheme 24.40) [132], Routes incorporating a tandem carbonylation step [133] and a direct arylation [117] process have subsequently been reported. 

There are very few examples of photolysis being used for preparation of a carbonyl ylide. The Dittami protocol follows work completed from his lab with aryl vinyl sulfides. Photolysis, followed by cycloaddition, led to the cycloadduct 305 in excellent yield and stereoselectivity. If the aryl vinyl ether 304 was subjected to irradiation in a mixed solution of toluene-methanol at 366 nm rather than a single solvent of toluene, cyclized product was obtained, but no cycloadduct was formed. If a simple phenyl aryl ether was subjected to the same tandem conditions, the cyclized product was generated, but no cycloadduct was detected. 

RXN13 Tandem Cyclization-Anion Capture (-Carbonylation) Process of Yne-Vinyl and Yne-Aryl Halides... 

Inter-Intra Tandem Processes Involving Pd-Catalyzed a-Arylation of Carbonyl Compounds with 1,2-Dibromoarenes. 1,2-Dibromoarenes have been shown to undergo Pd-catalyzed inter-intra tandem processes leading to the formation of cyclic compounds, as summarized in Scheme 28. In some examples, however, the cyclization process itself does not actually involve Pd-catalyzed a-arylation. It instead involves either an interesting diaryl ether formation (Sect, in.3.3) or intramolecular Heck reaction (Sect. IV.2.2). 

The total synthesis of the natural furano-fused dihydroisocoumarin (+)-monocerin was accomplished in 15 steps with a 15.5% overall yield starting from but-3-en-l-ol via tandem dihydroxylation-SN2 cyclization and a copper-catalyzed tandem cyanation-lactonization process (140BC5973). The formation of the 3,4-dihydroisocoumarin ring in the total synthesis of natural (+)- and unnatural (-)-scorzocreticin involves a palladium-catalyzed intramolecular carbonylation and lactonization of l-aryl-2-(2-iodoaryl) ethan-l-ol (14T8161). 

Using ortho-halogenated aryl aldehydes and MBH adducts as substrates, 2-carbonyl-1-indanols 136 have been synthesized in moderate to good yields via a one-pot, palladium-catalyzed tandem Heck-aldol reaction. Various MBH adducts were examined to find the scope and limitations of this process (Scheme 3.53). ... 

A palladium-catalyzed tandem Heck-aldol reaction in one-pot has been described to synthesize 2-carbonyl-1-indanol derivatives 47 from the reaction of or(/zo-halogenated aryl aldehyde 45 (X = I, Br) with MBH adduct 46. As shown in Scheme 4.16, 1-indanols 47 were produced as a mixture of diaster-eoisomers in a ratio of approximately 2 1 in moderate to good yields. Interestingly, MBH adduct derived from acrylonitrile could not afford the corresponding 1-indanol under identical conditions. 

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