Thermal Mitigation at User Equipment Based on Ambient Temperature

User equipment (UE) or other user devices employ thermal mitigation schemes that are responsive to the ambient temperature of the device. Such schemes can employ different levels or modes of thermal mitigation techniques based on ambient temperature, the thresholds that trigger the switch between levels or modes may be scaled based on ambient temperature, or a combination thereof

Six-membered ring systems: with O and/or S atoms

A large variety of publications involving O- and S-6-membered ring systems have appeared in 2017. The importance of these heterocyclic compounds is highlighted by the huge number of publications on the total synthesis of natural oxygen derivatives and of other communications dedicated to synthetic derivatives. Reviews on stereoselective organocatalytic synthesis of tetrahydropyrans (17EJO4666), of tetrahydropyrans and their application in total synthesis of natural products (17CSR1661), on the synthesis of the less thermodynamically stable 2,6-trans-tetrahydropyrans (17S4899), on enantioselective synthesis of polyfunctionalized pyran and chromene derivatives (17TA1462), and on enantioselective and racemic total synthesis of camptothecins, including the formation of their pyran-2-one ring (17SL1134), have appeared. Advances in the transition metal-catalyzed synthesis of pyran-2/4-ones (17TL263), N-heterocyclic carbene (NHC)-catalyzed achiral synthesis of pyran-2-one, coumarin and (thio)chromone derivatives (17OBC4731), on the synthesis and transformation of 2H-pyran-2-ones (17T2529) and 2-styrylchromones (17EJO3115) into other heterocyclic compounds, have been surveyed. The strategies to build up the tetrahydropyranyl core of brevisamide (17H(95)81) and the reactions of ketyl radicals, generated from carbonyl derivatives under transition-metal photoredox-catalyzed conditions, leading to isochromen- and chroman-type compounds (17CC13093) were disclosed. Developments in the synthesis of pentafluorosulfanyl(chromene and coumarin) derivatives (17TL4803), photoswitchable D9-tetrahydrocannabinol derivatives (17JA18206), and aminobenzopyranoxanthenes with nitrogen-containing rings (17JOC13626) have been studied.info:eu-repo/semantics/publishedVersio

Metal- and O₂‑Free Oxidative C–C Bond Cleavage of Aromatic Aldehydes

An oxidative C–C cleavage of aldehydes requiring neither metals nor O₂ was discovered. Homobenzylic aldehydes and α-substituted homobenzylic aldehydes were cleaved to benzylic aldehydes and ketones, respectively, using nitrosobenzene as an oxidant. This reaction is chemoselective for aromatic aldehydes, as an aliphatic aldehyde was unreactive under these conditions, and other reactive functionality such as ketones and free alcohols are tolerated. A mechanism accounting for the fate of the lost carbon is proposed

Synthesis of Spirooxindoles via the <i>tert</i>-Amino Effect

A new method is developed for the synthesis of spirooxindoles from amines and isatins via C–H functionalization. The reaction leverages the <i>tert</i>-amino effect to form an enolate–iminium intermediate via [1,5]-hydride shift followed by cyclization. Interestingly the hydride migrates to the N atom of a CN, which is atypical for hydride additions to imines

FeCl₃‑Catalyzed Allylation Reactions onto 3‑Hydroxy-2-oxindoles: Formal Total Syntheses of Bis-cyclotryptamine Alkaloids, (±)-Chimonanthine, and (±)-Folicanthine

An FeCl₃-catalyzed efficient strategy for the allylation reactions of 3-hydroxy-2-oxindoles with allyltrimethylsilane has been developed. The reaction affords a variety of 2-oxindoles having quaternary center at the pseudobenzylic position in an operationally simple and inexpensive procedure. Control experiments using enantioenriched 3-hydroxy-2-oxindole show that the reaction proceeds through in situ generated 2<i>H</i>-indol-2-one (<b>8</b>). The methodology presents an efficient and concise access to the pyrroloindoline alkaloids (±)-deoxyeseroline (<b>1a</b>), (±)-esermethole (<b>1b</b>), (±)-physostigmine (<b>1c</b>), (±)-phenserine (<b>1d</b>), and (±)-physovenine (<b>1e</b>). Eventually, we extrapolated the scope of this methodology to the formal total syntheses of dimeric cyclotyrptamine alkaloids (±)-chimonanthine (<b>3a</b>), (±)-folicanthine (<b>3c</b>), and (±)-calycanthine (<b>4</b>)

FeCl₃‑Catalyzed Allylation Reactions onto 3‑Hydroxy-2-oxindoles: Formal Total Syntheses of Bis-cyclotryptamine Alkaloids, (±)-Chimonanthine, and (±)-Folicanthine

An FeCl₃-catalyzed efficient strategy for the allylation reactions of 3-hydroxy-2-oxindoles with allyltrimethylsilane has been developed. The reaction affords a variety of 2-oxindoles having quaternary center at the pseudobenzylic position in an operationally simple and inexpensive procedure. Control experiments using enantioenriched 3-hydroxy-2-oxindole show that the reaction proceeds through in situ generated 2<i>H</i>-indol-2-one (<b>8</b>). The methodology presents an efficient and concise access to the pyrroloindoline alkaloids (±)-deoxyeseroline (<b>1a</b>), (±)-esermethole (<b>1b</b>), (±)-physostigmine (<b>1c</b>), (±)-phenserine (<b>1d</b>), and (±)-physovenine (<b>1e</b>). Eventually, we extrapolated the scope of this methodology to the formal total syntheses of dimeric cyclotyrptamine alkaloids (±)-chimonanthine (<b>3a</b>), (±)-folicanthine (<b>3c</b>), and (±)-calycanthine (<b>4</b>)