1,3-Bis(methylthio)propane, bis(methylthio)methane, and meso -4,6-dimethyl-1,3-dithiane were oxidized with 1-4 equivalents of hydrogen peroxide, meta -chloroperbenzoic acid, sodium periodate, or potassium permanganate, respectively, and the amounts of oxidized substrates (sulfoxides and/or sulfones) were determined NMR-spectroscopically. Sulfanyl groups in the former starting material turned out to

A general and convenient method for the direct transition-metal-free intermolecular chloro- difluoromethylthiolation of a variety of unactivated alkenes and alkynes has been described. This methodology exhibits good functional group tolerance and operationally simple. Mechanistic studies indicated that this is the electrophilic substitution mechanism, and the strong electrophilic difluoromethylthiolating

The photochemical fragmentation of N-aroylsulfonamides 9 (ASAP) is a powerful method for the preparation of various biaryls. Compounds 9 are easily accessible in two steps from amines by treatment with arenesulfonyl chlorides and aroyl chlorides. Many of these compounds were prepared for the first time. The irradiation takes place in a previously developed continuous-flow reactor using inexpensive

An efficient trimerization of ynals to diversely substituted 4 H -pyran constructs has been executed in water, under ambient regime employing micellar catalysis and is in alignment with the ideas of green and sustainable chemistry. The locus of the micellar reaction site has been probed through proton NMR studies. A general acid-mediated downstream rearrangement of the derived 4 H -pyrans to interesting

An efficient protocol for the synthesis of ring-fused quinazolinone derivatives through hydroxyalkyl radical-initiated cyclization was developed, providing a series of five- and six-membered ring-fused hydroxyl-containing quinazolinones in moderate to good yields. This reaction was conducted under metal-free conditions using dicumyl peroxide as the radical initiator. Notably, this is the first example

Symmetrical and unsymmetrical N , N ’-disubstituted as well as trisubstituted ureas/thioureas via the hydroamination of isocyanates/isothiocyanates, and various phosphathioureas via the hydrophosphination of isothiocyanates have been synthesized in good to excellent yields under catalyst-free and mild conditions. This protocol is also applicable for the efficient synthesis of chiral ureas and thioureas

Porous materials are important for various energy-related technologies such as catalysis and separation. While porous organic cage compounds are a rather recent addition to the field of porous materials, these discrete nanocavities have since emerged as a versatile functional-materials platform, facilitated by the solubility of the materials in common organic solvents. In contrast to other frameworks

The asymmetric synthesis of Si-stereogenic silanes has attracted great attention due to the increasing values of Si-containing functional molecules in synthetic chemistry, medicinal chemistry, and material chemistry. Merging organosilicon chemistry with transition metal catalyzed C–H approach has led to rich sets of new reactions holding great synthetic values. This review aims to summarize the advances

An efficient Rh-catalyzed catalytic method has been developed for selective C7 halogenation of N- pyrimidyl indolines with N -halosuccinimides (Cl, Br, I) to produce corresponding halides in good to excellent yields. The advantages of this strategy include broad substrate scope and excellent regioselectivity for C7 functionalization of indolines, and feasibility at gram scale level. Various control

2D polymers are a relatively new class of macromolecules. It is not astounding therefore that so far research focussed on how to provide access to this intriguing class of organic 2D materials, how to prove their existence, and how to assess their structural quality. Studies concerning the formation mechanism are comparatively scarce. We here collect and compare all the mechanistic information available

2-Aminobenzimidazole 10 , although a weak catalyst in the monomeric state, is a successful building block for effective artificial ribonucleases. In an effort to identify new building blocks with improved catalytic potential, RNA cleavage by a variety of heterocyclic amidines and guanidines has been studied. In addition to p K a values and steric effects, the energy difference between tautomeric forms

The alkaloid colchicine represents a prominent lead structure for the development of tubulin-binding chemotherapeutics. In the course of explorative research into semi-synthetic colchicinoids we stumbled upon a number of unexpected and mechanistically surprising transformations which reflect the very particular reactivity of the tropolone ether unit and its interplay with adjacent functional groups

Equilibrium constants for the formation of Wheland complexes from 1,3,5-tris(dialkylamino)benzenes and benzhydrylium ions (Ar 2 CH + ) have been determined photometrically in dichloromethane at 20 °C. The Lewis basicity of the ring carbons increases in the series trimorpholinobenzene < tripiperidinobenzene

Samarium diiodide (SmI 2 ) is a versatile single electron transfer (SET) reagent in organic synthesis. The advantages of SmI 2 arise from various additive induced tailoring of a reaction to obtain a desired product in a stereoselective fashion. In most instances, this reagent is used in stoichiometric amount, and this poses a significant environmental issue limiting a broader applicability of SmI 2

TLR2 agonists are at the forefront of vaccine research for a plethora of diseases, in particular they offer a promising tool for the treatment of cancer. A detailed knowledge of their structure-activity relationships informs the methodical design of vaccine constructs that include TLR2 agonists. Herein we report the design, synthesis, and biological evaluation of analogues of the TLR2 agonist Pam 2

A new strategy for the synthesis of 1,1-diaryl and triarylsubstituted alkenes has been developed utilizing B(C6F5)3-catalyzed hydroarylation of alkynes with phenols. The method provide a direct route to ortho -alkenylated phenols with both terminal and internal alkynes. The reactions show excellent regioselectivity, and especially, good stereoselectivity was observed for the hydroarylation of internal

Converting biomass into value added chemicals is of significant interest and we report an efficient hydrosilylation to convert levulinic acid to γ-valerolactone using cost-effective silanes such as PMHS and TMDS with B(C 6 F 5 ) 3 as catalyst. This metal free methodology works at room temperature reaching TONs and TOFs up to 16000 and 2000 h -1 . Insights into the reaction mechanism are reported.

An enantioselective organocatalytic addition of sodium bisulfite to ( E )-nitroalkenes has been developed catalyzed by a chiral bifunctional organocatalyst. The present methodology provides a variety of chiral β-nitroethanesulfonic acid compounds (17 examples) with excellent results: up to 99% yield and excellent enantioselectivity (up to 96% ee). The reaction tolerates (hetero)aryl and alkyl substituents

An unprecedented external oxidant-free electrochemical protocol for 1, 3-oxohydroxylation of donor-acceptor cyclopropane is disclosed. The strategy encompasses the activation of the labile π-electron cloud of the aryl ring to cleave the strained C sp 3 -C sp 3 bond of cyclopropane to afford the β -hydroxy ketones via insertion of molecular oxygen. More significantly, based on the detailed mechanistic

In this report, we describe a series of [2.2]paracyclophane-derived mono- and bimetallic N , C -palladacycles via regioselective ortho -palladation of amine-functionalized [2.2]paracyclophanes. Employing Pd(OAc) 2 followed by LiCl with the subsequent modular variations of Ph 3 P, Cy 3 P, and (Ph 2 PCH 2 ) 2 , this strategy allows to prepare structurally diverse and stable cyclophanyl-based planar and

Nucleophilic fluorination is one of the fundamental reactions in organic chemistry, as well as a convenient tool for the synthesis of fluorinated building blocks with a potential biological activity. In this minireview diethylaminosulfur trifluoride (DAST) mediated reactions leading to valuable building blocks and bioactive compounds will be discussed. We focused on results that have been published

Controlling the reactivity of ambident nucleophiles, nitrogen and sulfur as in an isothiocyanate by fine tuning the reaction parameters is a challenge in organic synthesis. A one pot multi-component protocol is described herein as an approach for construction of spirooxazolidine-2-thiones and spirooxothiolane-2-imines. In DBU mediated reaction, isatin, phenyl acetylenes, and aryl isothiocyanates undergo

The application of amino acids and small peptides as asymmetric organocatalysts in the aldol and conjugate addition reactions is a major breakthrough in past decade. The desired stereoselectivity in these reactions can be attained through tunable elements of diversity present in the amino acids/peptides. On this note, the current review highlights the organocatalytic aldol and conjugate addition by