Amino carbonylation palladium catalyzed

Different to Yu s work which was directed by the carboxy group [45], in 2012, Guan and coworkers described an alkyl amino-directed palladium-catalyzed C-H carbonylation of Af-alkylanilines to synthesize isatoic anhydrides (Scheme 3.22) [46]. Using 5 mol% Pd(OAc)2, 2.2 equiv. of Cu(OAc)2, and 0.2 equiv. of KI, isatoic... 

The palladium-catalyzed carbonylation of 4-amino-2-alkynyl carbonates 40 or 5-hydroxy-2-alkynyl carbonates 41 afforded a-vinylidene-/i-lactams 42 [60] or a-vinyl-idene-y-lactones 43 [61] in good yields (Scheme 3.25). The initially formed (allenyl-carbonyl)palladium(II) intermediates were trapped by the intramolecular amino- or hydroxy-nucleophiles to give 42 or 43. 

Palladium-catalyzed carbonylation of 2-iodoanilines 898 gives a 2-acylpalladium species that can be reacted with ketenimines to give 2,3-disubstituted (3//)-quinazolinones 899 <2000JOC2773>. When carbodiimides are used in place of the ketenimines under the same conditions, 2-amino-4(3//)-quinazolinones 900 are produced, and when isocyanates are employed, 2,4(l//,3//)-quinazolinediones 901 are obtained <2000JOC2773>. 

Since Wakamatsu serendipitously discovered amidocarbonylation while performing the cobalt-catalyzed hydroformyla-tion of olefins in 1971, this unique carbonylation reaction, affording a-amino acids directly from aldehydes, has been extensively studied.More recently, palladium-catalyzed processes have been developed to expand the scope of this reaction.The Pd-catalyzed amidocarbonylation has been applied to aldehydes,aryl halides, and imines. As a related reaction, lactamization " of aryl halides catalyzed by a rhodium complex has also been developed. 

This suggests that in the case that both intramolecular C- and 0-arylations are of geometrically equal possibility, the former preferentially takes place. The reaction of o-bromobenzaldehydes with dibenzylketones gives l,3-diaryl-2-naphthols that may be useful materials as bulky 0-ligands (Eq. 24) [62]. This cyclization involves palladium-catalyzed a-arylation and base-promoted dehy-drative condensation. Treatment of o-iodoanilines with ketones produces indole derivatives (Eq. 25) [63]. In this case, dehydrative condensation between the amino group and the carbonyl group occurs initially and the subsequent car-bopalladation (mechanism A) leads to the products. 

Watanabe, H., Hashizume, Y. and Uneyama, K. (1992) Homologation of trifluoroacetimidoyl iodides by palladium-catalyzed carbonylation. An approach to a-amino perfluoroalkanoic acids. Tetrahedron Lett., 33, 4333 4336. 

Gabriele et al. reported that the 2-oxazolidinones 462 were synthesized by the palladium-catalyzed oxidative carbonylation of the 2-amino- 1-alkanols 461 (Scheme 144).206 The aminocarbonyl palladium complex 463 is formed as an intermediate, and subsequent ring closure gives 462. 

The Marsden group has published a collection of articles detailing the synthesis of heteroatom containing C3 quatemized oxindoles [64—66]. The transformations involved the palladium-catalyzed intramolecular arylation of anilides bearing either amino or alkoxy functionality alpha to the anilide carbonyl. Under microwave conditions, a variety of 3-alkoxy-3-aryl, 3-amino-3-aiyl, or 3-amino-3-alkyloxin-doles have been prepared in racemic form. In one example, 3-indolyloxindole 1 7 was prepared in 65% yield (Scheme 28). 

Meyers and colleagues described the palladium-catalyzed carbonylative synthesis of oxazolines as early as 1992 [268]. Aryl or enol triflates made from the corresponding ketones and phenols, and also aryl halides, were used as starting materials and coupled with amino alcohols to give chiral a,)S-unsaturated or aryl oxazolines in good yields. Later on, Perry s group performed systematic studies on this one-pot, two-step process for the preparation of oxazolines (Scheme 2.37) [269, 270]. 

As early as 1985, a palladium-catalyzed carbonylative procedure for the synthesis of 1,4-benzodiazepines was reported. Starting from 2-haloanilines and amino acids, the desired seven-membered heterocycles were formed in moderate yields. More recently, an efficient, one-pot method for the synthesis of dibenzodiazepinone derivatives involving copper-catalyzed tandem C-N bond formation was reported. Using various halo amide and 2-iodoaniline derivatives as substrates, an array of dibenzcxliazepinone... 

N. Selander, A. Kipke, S. Sebehus, K. J. Szab6, J. Am. Chem. Soc. 2007, 129, 13723-13731. Petasis borono-Mannich reaction and allylation of carbonyl compounds via transient allyl boronates generated by palladium-catalyzed substitution of aUyl alcohols. An efficient one-pot route to stereodefmed a-amino acids and homoaUyl alcohols. 

M. BeUer, M. Eckert, W. A. Moradi, H. Nemnaim, Angew. Chem. Int. Ed 1999, 38, 1454—1457. Palladium-catalyzed synthesis of substituted hydantoins—a new carbonylation reaction for the synthesis of amino acid derivatives. 

Also with starting compounds containing two oxygen nucleophiles, both alkoxy/ amino carbonylation and cyclocarbonylation (carbonylative cydization to lactone) mechanisms can occur in sequence. Some bicydic y-lactones from parasitic wasps (Hymenoptera Braconidae) were synthesized by hydrolytic kinetic resolution of epoxides and palladium(II)-catalyzed hydroxycyclization-carbonylation-lactoniza-tion of enediols. For example, cis- and trans-5-n-hexyl-tetrahydrofuro[3,2-b]furan-2 (3H)-ones 75 and 76, with the (3aR,5R,6aR) and (3aS,5R,6aS) configurations, respectively, were acquired in six steps from the inexpensive, readily available ridnoleic add 74 (Scheme 13.48) (89). 

In addition, the palladium-catalyzed C-H carbonylation is also useful to construct pyranone derivatives. In 2011, Yu s group reported a Pd(II)-catalyzed ortho-C-H carbonylation reaction of phenethyl alcohol derivatives to give 1-isochromanones by connecting the aryl moiety and alcohol with incorporated carbonyl group (Scheme 3.24) [49]. A wide range of functionahties such as methoxy, fluoro, chloro, and bromo are tolerated under the typical condition and afford various 1-isochromanones in moderate to good yields. The A-protected amino acids are supposed to reduce the rate of Pd(II) reduction in the presence of CO in this work. 

Inokuchi E, Narumi T, Niida A, Kobayashi K, Tomita K, Oishi S, Ohno H, Fujii N. Efficient synthesis of trifluoromethyl and related trisubstituted alkene dipeptide isosteres by palladium-catalyzed carbonylation of amino acid derived allyUc carbonates. J. Org. Chem. 2008 73 3942-3945. 

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