Synthesis of Polyfluoroalkyl Aryl Ethers Mediated by Sulfuryl Fluoride as a Traceless Activator.

Herein, we report the metal-free synthesis of polyfluoroalkyl aryl ethers via nucleophilic substitution of fluorosulfonates, obtained in one pot by bubbling of sulfuryl fluoride (SOF). Polyfluoroalkyl aryl ethers are present in a variety of biologically active compounds, but previous methods for accessing them required metal catalysts or harsh conditions. With this method, their synthesis is possible under mild conditions and with a short reaction time (30 min) from commercially available starting materials and in yields of ≤97%.

New Chemical Transformations Involving SO F -Mediated Alcohol Activation.

Sulfuryl fluoride is a gas produced on a multi-ton scale for its use as a fumigant. In the last decades, it has gained interest in organic synthesis as a reagent with unique properties in terms of stability and reactivity when compared to other sulfur-based reagents. Sulfuryl fluoride has not only been used for sulfur-fluoride exchange (SuFEx) chemistry but also encountered applications in classic organic synthesis as an efficient activator of both alcohols and phenols, forming a triflate surrogate, namely a fluorosulfonate.

Ruthenium-Catalyzed Synthesis of Aryl and Alkenyl Halides from Fluorosulfonates.

Aryl and alkenyl halides are widely used as key intermediates in organic synthesis, particularly for the formation of organometallic reagents or as radical precursors. They are also found in pharmaceutical and agrochemical ingredients. In this work, the synthesis of aryl and alkenyl halides from the corresponding fluorosulfonates using commercially available ruthenium catalysts is reported.

Traceless N-Polyfluoroalkylation of Weakly Nucleophilic Nitrogen Containing Compounds.

Here we report an efficient access to high-value N-polyfluoroalkyl anilines, primary polyfluoroalkylamines and N,N-bis(polyfluoroalkyl)amines, via N-polyfluoroalkylation of sulfonamides and phthalimide derivatives using sulfuryl fluoride (SO F ). The in situ formation of polyfluoroalkyl fluorosulfonates from commercially available fluorinated alcohols and economical sulfuryl fluoride is highly advantageous given that some polyfluoroalkyl halides are ozone-depleting substances (ODS) regulated by the Montreal protocol. This general method is applied to the polyfluoroalkylation of a variety of sulfonamides, N-sulfonyl carbamates and phthalimide with a wide tolerance of functional groups.

Synthesis of -Substituted 5- and 6-Membered Benzo-Phostams: 2,3-Dihydro-1-1,2-benzazaphosphole 2-Oxides and 2,3-Tetrahydro-1-1,2-benzazaphosphinine 2-Oxides.

Several approaches were developed for the preparation of phosphorus-substituted 5- and 6-membered benzophostams. Carbodiimide-promoted cyclization of zwitterionic aminophosphinates derived from a nitrobenzene precursor accomplished the cyclization in good yields. Alternatively, a novel copper-catalyzed cross-coupling between a phosphonamide and a bromobenzene precursor produced the heterocycles in moderate to good yields.

SOF-Mediated -Alkylation of Imino-Thiazolidinones.

The -alkylation of ambident and weakly nucleophilic imino-thiazolidinones has been developed substitution with alkyl fluorosulfonates. These reactive electrophiles are obtained through the transformation of nontoxic, economic, and commercially available alcohol derivatives on exposure to SOF gas. The use of electron-withdrawing groups and DMAc as solvent affords a ()- and -endocyclic selectivity for the easy introduction of a variety of alkyl and polyfluoroalkyl chains.

Synthesis of 3-Amino-5-fluoroalkylfurans by Intramolecular Cyclization.

A synthesis to access rarely described 3-amino-5-fluoroalkylfurans has been developed by cyclization of easily accessible fluorovinamides. This method is rapid and simple and affords the desired furans as hydrochloride salts in quantitative or nearly quantitative yields. It is compatible with four different fluorinated groups (-CF, -CFCF, -CHF, and -CFCl) and a wide range of substituents on the amine.

Validating the use of fecal glucocorticoid metabolite analysis to assess the adrenocortical activity of the zoo-housed Sichuan takin (Budorcas taxicolor tibetana).

With limited information known about the zoo-housed Sichuan takin (Budorcas taxicolor tibetana), there is a need to gain more knowledge about their basic physiology to be able to better assess their well-being. Our goal was to develop noninvasive methods to evaluate stress physiology in the Sichuan takins housed under human care. The objectives were: (1) validate the use of fecal glucocorticoid metabolite (FGM) analysis to monitor adrenocortical activity and (2) determine the relationship between FGM concentrations and changes in various factors including environmental conditions, reproductive hormones, and social factors.

Deprotonative Functionalization of the Difluoromethyl Group.

The functionalization of 3-(difluoromethyl)pyridine has been developed via direct deprotonation of -CHF with a lithiated base and subsequent trapping with various electrophiles in THF. quenching gives access to 3-pyridyl-CF-SiMePh as a new silylated compound, which can be postfunctionalized with a fluoride source to obtain a larger library of 3-(difluoroalkyl)pyridines that could not be accessed via direct deprotonation.

Characterizing adrenocortical activity in zoo-housed southern three-banded armadillos (Tolypeutes matacus).

Improving the husbandry in the southern three-banded armadillo (Tolypeutes matacus) through gaining knowledge of its stress physiology is imperative to maintaining a healthy, zoo-housed population. Our objectives were to: 1) validate the use of fecal hormone analysis for monitoring adrenocortical activity using both an adrenocorticotropic hormone (ACTH) challenge and biological events; and 2) characterize longitudinal adrenocortical activity in male and female southern three-banded armadillos. An ACTH injection was given intra-muscularly to one male (4IU/kg; 5.

Improved procedure for the synthesis of enamine N-oxides.

An improved procedure for the preparation of enamine N-oxides involving aminolysis of epoxides, chlorination, N-oxidation, and dehydrochlorination is described. Although isolated beta-chloroamine N-oxides are prone to rearrangements when isolated, these side reactions can be slowed by the presence of stabilizing organic acids. The scope and limitations of this strategy are discussed.

Direct asymmetric catalytic 1,2-addition of RZnX to aldehydes promoted by AlMe3 and reversal of expected stereochemistry.

Addition of AlMe3 to commercial THF solutions of RZnX (R = aryl, functionalised aryl, vinyl; X = Br, I) simultaneously promotes Schlenk equilibria (leading to competent nucleophiles) and the formation of an Al-Zn-ligand catalyst delivering 80-90% ee for Ar(1)CH(OH)Ar(2) formation from aldehydes.