Desulfitative Cross-Coupling of Protecting Group-Free 2-Thiouracil Derivatives with Organostannanes

We here report a unique and efficient copper bromide mediated pallado-catalyzed coupling of protecting group-free 2-thiouracil derivatives with organostannanes. The nature of the copper appears to be crucial for successful cross coupling

Synthesis of C3-Substituted 4-Azaindoles: An Easy Access to 4-Azamelatonin and Protected 4-Azatryptophan

C3-Substituted-4-azaindoles were synthesized from pyridylacetonitriles in a two-step sequence allowing the easy introduction of a range of substituents. This strategy permits the rapid synthesis of 4-azamelatonin and a protected 4-azatryptophan

Synthesis of C3-Substituted 4-Azaindoles: An Easy Access to 4-Azamelatonin and Protected 4-Azatryptophan

C3-Substituted-4-azaindoles were synthesized from pyridylacetonitriles in a two-step sequence allowing the easy introduction of a range of substituents. This strategy permits the rapid synthesis of 4-azamelatonin and a protected 4-azatryptophan

Synthesis of 4- and 6-Azaindoles via the Fischer Reaction

Contrary to the common idea that Fischer indole cyclization often cannot be effectively applied to the synthesis of the corresponding azaindoles, we show that this approach can be actually very efficient for the formation of 4- and 6-azaindoles bearing an electron-donating group on the starting pyridylhydrazines. Two 4-azaindole natural product analogues were synthesized in a few steps and very good overall yields

Sequential Michael Addition and Enamine-Promoted Inverse Electron Demanding Diels–Alder Reaction upon 3‑Vinyl-1,2,4-triazine Platforms

An original one-pot Michael addition-<i>ih</i>DA/<i>r</i>DA sequence was achieved from 3-vinyl-1,2,4-triazine platforms used as unprecedented Michael acceptors. This sequence provides a novel access to functionalized [2,3]-fused pyridine derivatives via a unique enamine promoted intramolecular <i>ih</i>DA reaction of 1,2,4-triazine intermediates

An Efficient Synthetic Approach to Highly Conjugated Porphyrin-Based Assemblies Containing a Bipyridine Moiety^†

An efficient and potential stepwise strategy involving the mixed sequence of Stille and Wittig−Horner reactions was used for the preparation of a polyene-substituted bis-porphyrin incorporating a bipyridine moiety

Palladium-Catalyzed C3-Arylations of 1<i>H</i>- and 2<i>H</i>‑Pyrazolo[4,3‑<i>b</i>]pyridines on Water

Direct C3-arylation of 1H-pyrazolo­[4,3-b]­pyridines and direct C3-arylation of 2H-pyrazolo­[4,3-b]­pyridines in water has been developed. A new protocol for a sequential C3-arylation procedure on a mixture of 1H- and 2H-pyrazolo­[4,3-b]­pyridines followed by in situ PMB cleavage has also been achieved. This procedure led to unprotected (NH) C3-arylated 1H-pyrazolo­[4,3-b]­pyridines in good yields

Copper(I)-Promoted Palladium-Catalyzed Cross-Coupling of Unsaturated Tri-<i>n</i>-butylstannane with Heteroaromatic Thioether

Palladium-catalyzed cross-coupling of vinyl- and arylstannanes with π-electron-deficient heteroaromatics was performed in good yields. This Stille-type reaction was carried out with a methylthioether function as an electrophile in the presence of a copper(I) bromide-dimethyl sulfide complex

Oxazolinethiones and Oxazolidinethiones for the First Copper-Catalyzed Desulfurative Cross-Coupling Reaction and First Sonogashira Applications

Cyclic thionocarbamates, namely chiral oxazolidinethiones (OZT) and aromatic oxazolinethiones (OXT), were involved, for the first time, in Sonogashira cross-coupling. A cooperative effect of two different copper (I) speciesCuI and CuTCaccounts for this new copper-catalyzed desulfurative carbon−carbon cross-coupling reaction. This cooperative reactivity could also be extended to other copper (I) catalysts

Oxazolinethiones and Oxazolidinethiones for the First Copper-Catalyzed Desulfurative Cross-Coupling Reaction and First Sonogashira Applications

Cyclic thionocarbamates, namely chiral oxazolidinethiones (OZT) and aromatic oxazolinethiones (OXT), were involved, for the first time, in Sonogashira cross-coupling. A cooperative effect of two different copper (I) speciesCuI and CuTCaccounts for this new copper-catalyzed desulfurative carbon−carbon cross-coupling reaction. This cooperative reactivity could also be extended to other copper (I) catalysts