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An efficient procedure for the copper-catalyzed cross-coupling between a broad range of cyanamides and iodoalkenes is reported. Upon reaction with catalytic amounts of copper(I) iodide and 2,2'-bisimidazole in the presence of cesium carbonate in DMF at 80 °C, a fast, regioselective, and stereoretentive cross-coupling occurs. This reaction, which was found to have a broad substrate scope, provides the first general entry to N-alkenylcyanamides, building blocks that hold great synthetic potential. [ABSTRACT FROM AUTHOR]

CuI/DMSO-mediated intramolecular cycloacetalization/ketalization of o-carbonyl allylbenzenes has been achieved for constructing [6,6,5]-tricycles having a ketal motif in good yields. The expeditious one-step route provides a three C-O bond formation. The key products with the structural framework of a benzofused dioxabicyclo[3.2.1]octane core have been confirmed by X-ray crystallographic analysis. Synthesis of dihydroisocoumarin has been studied. [ABSTRACT FROM AUTHOR]

(S,R)-N-PINAP was identified to be the chiral ligand for highly enantioselective CuI-catalyzed reaction of tetrahydroisoquinolines (THIQs), alkynes, and 2-bromobenzaldehyde derivatives. This enables us to accomplish the first asymmetric total synthesis of 12 natural 13-methyltetrahydroprotoberberine (13-MeTHPB) alkaloids in only three catalytic steps with 47-64% overall yields. In addition, the Pd-catalyzed reductive Heck cyclization was successfully extended to three Pd-catalyzed domino reactions (Heck/Suzuki, Heck/Sonogashira, and Heck/Heck), which greatly expands the synthetic utility of this catalytic strategy and allows expeditious access to 13-substituted tetrahydroprotoberberines for further bioactivity evaluation. [ABSTRACT FROM AUTHOR]

An enolate driven copper-mediated cross-coupling process enabled cheaper and greener access to the key pentacyclic intermediates required for the enantiospecific total synthesis of a number of C-19 methyl substituted sarpagine/macroline indole alkaloids. Replacement of palladium (60-68%) with copper iodide (82-89%) resulted in much higher yields. The formation of an unusual 7-membered cross-coupling product was completely inhibited by using TEMPO as a radical scavenger. Further functionalization led to the first enantiospecific total synthesis of macrocarpines D and E. [ABSTRACT FROM AUTHOR]

Copper iodide catalyzes the conjugate addition of organometallic and heteroatom nucleophiles to isocyano enones to afford oxazoles. A range of enolates, metalated nitriles, amines, and thiols undergo catalyzed conjugate addition to cyclic and acyclic oxoalkene isocyanides. Mechanistic studies suggest that copper complexation facilitates the nucleophilic attack on the isocyano enone to generate an enolate that cyclizes onto the isocyanide leading to a variety of substituted acyclic or ring-fused oxazoles. [ABSTRACT FROM AUTHOR]

An efficient and general system for the halogen exchange reaction in alkenyl halides has been developed. Upon reaction with catalytic amounts of copper iodide and trans-N,N'-dimethylcyclohexane-1,2-diamine in the presence of tetramethylammonium chloride or bromide, a wide range of easily accessible alkenyl iodides can be smoothly transformed to their far less available chlorinated and brominated derivatives in excellent yields and with full retention of the double bond geometry. This reaction also enables the chlorination of bromoalkenes and could be extended to the use of gem-dibromoalkenes. [ABSTRACT FROM AUTHOR]

A novel CuI/BF3·Et2O/O2-mediated reaction utilizing ketones and benzylamines for the construction of substituted imidazoles in one step under mild conditions has been demonstrated. This protocol involved the removal of eight hydrogen atoms, the functionalization of four C(sp3)–H bonds and three new C–N bond formations. [ABSTRACT FROM AUTHOR]

A new method for C–C and C–N bond formation of heteroaromatics and C(sp3)–H alkanes was developed with high regioselectivity. The reaction occurred on C8 to give 8-cylcoakylpurines by C–C bond formation only promoted by tBuOOtBu, while it occurred on the amino group to give N6-alkylated purines by C–N bond formation when 2 equiv of CuI were added. A reaction mechanism was also proposed based on our preliminary experimental data. [ABSTRACT FROM AUTHOR]

An efficient synthesis of 2- or 4-iododibenzofurans through CuI-mediated sequential iodination/cycloetherification of two aromatic C–H bonds in o-arylphenols has been developed. Both the preexisting electron-withdrawing groups (NO2, CN, and CHO) and the newly introduced iodide are readily modified for a focused dibenzofuran library synthesis. Mechanistic studies and DFT calculations suggest that a Cu(III)-mediated rate-limiting C–H activation step is involved in cycloetherification. [ABSTRACT FROM AUTHOR]

In the presence of catalytic amount of copper iodide, a remote amide-assisted intramolecular arylation followed by alkylation leads to a general and flexible synthetic method toward the synthesis of medicinally interesting hexahydropyrroloindole alkaloids. [ABSTRACT FROM AUTHOR]

A pH-controlled fluorescence switch based on a core-substituted naphthalenediimide compound (NDI-DBU) was constructed. The novel pentacyclic compound (NDI-DBU) was derived from naphthalenediimide (NDI) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in only one synthetic operation, catalysized by CuI. [ABSTRACT FROM AUTHOR]

New difunctionalized and fluoroalkylated silyl reagents have been prepared that react with silver and copper salts to afford active catalysts that can be used to synthesize arylated fluoroalkyl bromide building blocks. It has been shown that the [(phen)Ag(CF2)nBr] intermediates are capable of transferring both the phenanthroline ligand and the fluoroalkyl bromide chain to copper iodide, eliminating the need for a preligated copper salt precursor. The methodology is compatible with various chain lengths of the fluoroalkyl halide functionality. [ABSTRACT FROM AUTHOR]

The direct C−H alkynylation of azoles with alkynyl bromides proceeds efficiently in the presence of a nickel-based catalyst system. The reaction enables the introduction of various alkynyl groups bearing aryl, alkenyl, alkyl, and silyl substituents to the azole cores. In some cases, addition of a catalytic amount of CuI is observed to accelerate the direct coupling dramatically. [ABSTRACT FROM AUTHOR]

A method for the direct arylation of benzotriazepines is reported, employing an aryl iodide as the coupling partner, copper iodide as the catalyst, and lithium tert-butoxide as the base. A variety of electron-rich, electron-poor, and sterically hindered aryl iodides are compatible with the reaction conditions. The arylation reaction can also be performed outside a glovebox in air without a significant decrease in yield. Furthermore, convenient microwave conditions for carrying out this transformation are reported. [ABSTRACT FROM AUTHOR]

A versatile methodology for the diastereo- and enantioselective domino reductive-aldol cyclizations is reported. By using a copper (I)/diphosphane ligand, various five- and six-membered rings were generated with good to excellent diastereo- and enantioselectivities (cis:trans up to 100:0 and ee up to 95%). [ABSTRACT FROM AUTHOR]

We present here our results of the efficient copper-catalyzed cyclizations of chalcogenoenynes and establish a route to obtain 3-substituted chalcogenophenes in good to excellent yields. In addition, the obtained chalcogenophenes were readily transformed to more complex products using the palladium-catalyzed cross-coupling reactions with boronic acids to give Suzuki-type products in good yields. [ABSTRACT FROM AUTHOR]

Palladium−copper-promoted Stille-type cross-coupling reactions between α-stannylphospholes and α-iodophospholes afforded α,α′-linked oligophospholes and polyphosphole efficiently. It has been revealed that the polyphosphole P-oxide possesses an extremely narrow band gap and a high electron-accepting ability as compared to polythiophene. [ABSTRACT FROM AUTHOR]

The key C13−C23 fragment toward the total synthesis of iriomoteolide-1a (1) has been constructed from an 1,2-acetonide containing aldehyde 5via a Julia−Kocienski olefination with the C16−C23 segment 6. The key step involves stereoselective introduction of the C29 methyl group by a highly efficient CuI-Tol-BINAP-catalyzed asymmetric conjugate addition of methylmagnesium bromide to an α,β-unsaturated ester. [ABSTRACT FROM AUTHOR]

The sequential use of a single CuIcatalyst enables the one-pot synthesis of N′-arylaminooxazolidinones through a Lewis acid catalyzed rearrangement followed by an N-arylation reaction. Contrary to previous reports, the formation of a cis-fused 5,5-membered ring system occurs during the rearrangement, as proven by X-ray crystallography. [ABSTRACT FROM AUTHOR]

The copper(I) iodide catalyzed phosphine/aryl halide coupling procedure of Buchwald et al. provides modular, robust, and scaleable access to phosphinooxazoline (PHOX) ligands. The advantages of this method are highlighted by the convenient synthesis of PHOX ligands with varied steric and electronic properties, which would be challenging to synthesize by other protocols. [ABSTRACT FROM AUTHOR]