The reaction of Meldrum's acid, pyrrolide, and allyl carbonates allows a multicomponent decarboxylative coupling to form allylated acyl pyrroles. This strategy is made possible by the in situ formation of β-oxo carboxylates from Meldrum's acid. Subsequent decarboxylative enolate formation and electrophilic allylation complete the reaction. Addition of benzylidene malononitriles as good Michael ...

4.2.8. Reductive Coupling 3109 5. Reaction of Aromatic Compounds 3110 5.1. Electrophilic Substitutions 3110 5.2. Radical Substitution 3111 5.3. Oxidative Coupling 3111 5.4. Photochemical Reactions 3111 6. Reaction of Carbonyl Compounds 3111 6.1. Nucleophilic Additions 3111 6.1.1. Allylation 3111 6.1.2. Propargylation 3120 6.1.3. Benzylation 3121 6.1.4. Arylation/Vinylation 3121 6.1.5. Alkynylat...

A new method for the synthesis of 3-arylindoles has been developed by visible light mediated dual gold/photoredox catalysis. This transformation has many features such as cascade catalysis, high efficiency, redox-neutral reaction conditions and good functional group tolerance. The reaction proceeds through the photoredox-promoted formation of an electrophilic arylgold(iii) intermediate that und...

The reaction of Hg(CF3CO2)2 with metalloporphyrins produces mercurated porphyrins regioselectively, the reaction, surprisingly occurring at the most hindered betaB-position; this behavior is in marked contrast to the usual electrophilic substitution reactions of porphyrins, whose reactions produce meso-substituted porphyrins; the obtained mercurated porphyrins are active to transition metal-cat...

A novel sequence of Sonogashira coupling and electrophilic addition to an ynone, with concomitant deprotection and cyclocondensation, opens a new one-pot synthesis of 3-halofurans; the method can be readily elaborated to a new sequential Sonogashira-addition-cyclocondensation-Suzuki reaction to furnish 2,3,5-trisubstituted furans in a one-pot fashion.

Copper catalysts enable the electrophilic carbofunctionalization of alkynes with vinyl- and diaryliodonium triflates. The new process forms highly substituted alkenyl triflates from a range of alkynes via a pathway that is opposite to classical carbometalation. The alkenyl triflate products can be elaborated through cross-coupling reactions to generate synthetically useful tetrasubstituted alke...

The use of enol phosphinates as electrophiles for cross-coupling reactions has been explored. Both boronic acids (Suzuki-Miyaura reaction) and stannanes (Stille reaction) couple efficiently with lactam derived phosphinates.

background: bonding of molar tubes is becoming more popular in orthodontics. occasionally, these bonding are done on posterior porcelain crowns or bridges. the purpose of this study was to evaluate the shear bond strength of buccal tubes on feldspathic porcelain crowns with two different methods. materials and methods: forty porcelain right molar crowns were fabricated for this study. the crown...

The regioselective functionalization of aza-ullazines has been successfully realized for the first time by either metalation using BuLi-containing aggregates (BuLi-LiDMAE) or electrophilic substitution. Mono and di-bromo-derivatives were obtained in good to excellent yields further converted into aryl alkynyl azaullazine derivatives Suzuki Sonogashira cross-coupling reactions.

The first syntheses of 4-methyl-2-t-butyland 2-methyl-4.6-di-t-butyl-indole are described. Rates of diazocoupling at the 3-position of both these compounds together with those for 2-methyland 2-t-butyl-indole are reported for various para-substituted arenediazonium ions in mixed aqueous and some aprotic solvents a t 25". The kinetic behaviour of 2-methylindole is examined in detail and it is sh...