Showing papers on "Heck reaction published in 1991"
124 citations
TL;DR: In this paper, the stereoselective total synthesis of the title compound starting from D-glucose is described, and the key steps in this synthesis are Ferrier rearrangement to construct the optically active cyclohexenone (C-ring), and Pd-catalyzed intramolecular Heck reaction to build the phenanthridone skeleton.
68 citations
TL;DR: In this article, a series of palladium catalysed cyclisations with substrates possessing an allylic alcohol moiety was investigated, and it was shown that it is possible to combine an alkylation and a cyclisation process using the same palladium catalyst system.
55 citations
TL;DR: The characteristic 2-azabicyclo[3.3.1]nonane substructure of Strychnos alkaloids can be constructed rapidly and stereospecifically using an intramolecular Heck reaction as mentioned in this paper.
51 citations
TL;DR: The Pd(0)-catalyzed polycyclizations 1 → 3 + 4, 5 → 9 and 6 → 10 are described in this paper, where the stereospecifity of these transformations is ascribed to an intramolecular suprafacial "palladium-ene" process followed by one to two Heck-insertions, proceeding with retention of configuration at the metalated carbon.
Abstract: The Pd(0)-catalyzed polycyclizations 1 → 3 + 4, 5 → 9 and 6 → 10 are described. The stereospecifity of these transformations is ascribed to an intramolecular suprafacial “palladium-ene” process followed by one to two “Heck-insertions” proceeding with retention of configuration at the metalated carbon.
37 citations
TL;DR: Several arylacetaldehydes 5 were synthesized in moderate yields via Heck reaction of acrylamide (1) with substituted iodobenzenes 2 in the presence of the polymeric catalyst P-phenyl-(1,10-phenanthroline)-palladium(O) [P-ph-phen.Pd(O)] followed by Hofmann reaction and subsequent hydrolysis as discussed by the authors.
Abstract: Several arylacetaldehydes 5 were synthesized in moderate yields via Heck reaction of acrylamide (1) with substituted iodobenzenes 2 in the presence of the polymeric catalyst P-phenyl-(1,10-phenanthroline)-palladium(O) [P-ph-phen.Pd(O)] followed by Hofmann reaction and subsequent hydrolysis
32 citations
TL;DR: The reaction of 3-iodotropolone with styrenes (styrene, p-methoxystyrene and 2-vinylpyridine) to give 3-styryl, 3-(2-carboxyvinyl)-, and 3-(3-substituted 1-propenyl)tropolones, respectively, was studied in this article.
Abstract: The reactions of 3-iodotropolone with styrenes (styrene, p-methoxystyrene, and 2-vinylpyridine), methyl acrylate, and allylic compounds (methyl 3-butenoate, 3-butenenitrile, 1-allyl-3,4-dimethoxybenzene, and 1-allyl-3,4-methylenedioxybenzene) were carried out, according to the modified Heck’s procedure, to give 3-styryl-, 3-(2-carboxyvinyl)-, and 3-(3-substituted 1-propenyl)tropolones, respectively. Similarly, 4-bromo- or 5-bromotropolone was made to react with these olefins to yield 4-styryltropolone or the corresponding 5-(2-substituted vinyl)- and 5-(3-substituted 1-propenyl)tropolones. Substitution of 2-chlorotropone by styrenes produced 2-styryltropones. Extension of the vinylation to 2-amino-6-bromoazulenes, ethyl 3-bromo-1-azulenecarboxylate, and diethyl 2-chloro-1,3-azulenedicarboxylate resulted in a similar substitution.
20 citations
TL;DR: A biphenomycin B analogue has been prepared using the double Heck coupling of 3,3′-diiodo-4,4′-dimethoxybiphenyl and two orthogonally protected 2-amidoacrylates followed by two peptide bond forming steps for the incorporation of L-lysine as the middle amino acid residue.
Abstract: A biphenomycin B analogue has been prepared using the double Heck coupling of 3,3′-diiodo-4,4′-dimethoxybiphenyl and two orthogonally protected 2-amidoacrylates followed by two peptide bond forming steps for the incorporation of L-lysine as the middle amino acid residue.
13 citations
TL;DR: In this paper, the reaction of 5-iodouridine with esters of acrylic acid in the palladium-catalysed Heck reaction was used to generate a series of esters for the acid (E) -5- (2-carboxyvinyl)uridine.
Abstract: The reaction of 5-iodouridine with esters of acrylic acid in the palladium-catalysed Heck reaction was used to generate a series of esters of the acid (E) -5- (2-carboxyvinyl)uridine in poor to moderate yield. An alternative method starts from the acid by protection of the sugar moiety followed by in situ generation of the acid chloride then ester formation followed by simultaneous sugar deprotection. Treatment of the methyl ester with ammonia and methylamine gave the corresponding amides, while treatment with dimethylamine gave 5-(1-dimethylamino-2-carboxy)ethyluridine as the major product.
10 citations
TL;DR: Tributyltin hydride-induced radical cyclization of the (Z)-α-benzylidene-β-(o-bromobenzyl)-γ-lactone (16) gave the 6-endo cyclization product, (±)-deoxyisopicropodophyllin (18), and the 5-exo cyclisation product.
Abstract: Tributyltin hydride-induced radical cyclization of the (Z)-α-benzylidene-β-(o-bromobenzyl)-γ-lactone (16) gave the 6-endo cyclization product, (±)-deoxyisopicropodophyllin (18), and the 5-exo cyclization product (19). On the other hand, the intramolecular Heck reaction of 16 provided (±)-γ-apopicropodophyllin (20) as a sole cyclization product
9 citations
Journal Article•
TL;DR: An extremely important role for the tertiary amine in the reduction of Pd(II) formed as result of the reductive transformations of the aryl halide in the Heck reaction was shown in this paper.
Abstract: An extremely important role is shown for the tertiary amine in the reduction of Pd(II) formed as result of the reductive transformations of the aryl halide in the Heck reaction. The dependence of the rate on the nature of the base is explained.
TL;DR: In this article, a new fulvene synthesis results from the palladium-catalyzed [2 + 2+2] annulation of 1 mol of a β-substituted vinyl iodide and 2mol of a monosubstitized acetylene.
Abstract: A new fulvene synthesis results from the palladium-catalyzed [2+2+2] annulation of 1 mol of a β-substituted vinyl iodide and 2 mol of a monosubstituted acetylene. This variant of the Heck reaction tolerates a wide range of substrate substituents with the best results obtained by using the catalyst, Pd(CH 3 CN) 2 Cl 2 . Addition of Cu I I to the reaction affords high yields of 1,3-enyne and no fulvene. A [6.5]spiro system is formed from 4-tert-butyl-1-cyclohexenyl triflate and a biphenyl is formed from 1-aryl-1-bromoethene under these conditions. A mechanism for this novel fulvene synthesis is proposed
TL;DR: The reaction of 3-iodotropolone with styrenes (styrene, p-methoxystyrene and 2-vinylpyridine) to give 3-styryl, 3-(2-carboxyvinyl)-, and 3-(3-substituted 1-propenyl)tropolones, respectively, was studied in this article.
Abstract: The reactions of 3-iodotropolone with styrenes (styrene, p-methoxystyrene, and 2-vinylpyridine), methyl acrylate, and allylic compounds (methyl 3-butenoate, 3-butenenitrile, 1-allyl-3,4-dimethoxybenzene, and 1-allyl-3,4-methylenedioxybenzene) were carried out, according to the modified Heck’s procedure, to give 3-styryl-, 3-(2-carboxyvinyl)-, and 3-(3-substituted 1-propenyl)tropolones, respectively. Similarly, 4-bromo- or 5-bromotropolone was made to react with these olefins to yield 4-styryltropolone or the corresponding 5-(2-substituted vinyl)- and 5-(3-substituted 1-propenyl)tropolones. Substitution of 2-chlorotropone by styrenes produced 2-styryltropones. Extension of the vinylation to 2-amino-6-bromoazulenes, ethyl 3-bromo-1-azulenecarboxylate, and diethyl 2-chloro-1,3-azulenedicarboxylate resulted in a similar substitution.