1192233-76-3Relevant academic research and scientific papers
A well-defined (POCOP)Rh catalyst for the coupling of aryl halides with thiols
Timpa, Samuel D.,Pell, Christopher J.,Ozerov, Oleg V.
, p. 14772 - 14779 (2014)
This article describes a well-defined pincer-Rh catalyst for C-S cross-coupling reactions. (POCOP)Rh(H)(Cl) serves as an active precatalyst for the coupling of aryl chlorides and bromides with aryl and alkyl thiols under reasonable conditions (3% mol cat., 110 °C, 2-24 h, >90% yield). For select substrates, >90% yields were obtained with catalyst loading as low as 0.1%. Key mechanistic intermediates have been isolated and fully characterized, including (POCOP)Rh(Ph)(SPh) (6a) and (POCOP)Rh(SPh2) (6b). The aryl/bis(phosphinite) (POCOP)Rh system has been shown to favor aryl thiolate reductive elimination at elevated temperatures and in some cases at room temperature, compared with the analogous diarylamido/bis(phosphine) (PNP)Rh pincer system. Concerted reductive elimination has been studied with 6a directly and in the presence of aryl bromide and aryl chloride traps. This investigation demonstrates a clear rate dependence on aryl chloride concentration during catalysis, a dependence that is absent when using aryl bromides. The rate of catalysis is dramatically reduced or brought to zero for ortho-tolyl halides, which can be traced to slower C-S coupling and slower carbon-halogen oxidative addition for ortho-substituted aryls. The influence of the sterics in the thiol component is less straightforward. The S-H oxidative addition product (POCOP)Rh(H)(SPh) (16) has been fully characterized and its reactivity has been examined, resulting in the isolation of the sodium-thiolate adduct (POCOP)Rh(NaSPh) (19). The solid-state structure of 19 shows Na interactions not only with sulfur, but also with a neighboring Rh and the chelating aryl carbon of the pincer framework. The reactivity of 16 and 19 indicates that these potential side products should not hinder catalysis.
LONG-CHAIN FATTY ACYL ELONGASE INHIBITOR COMPRISING ARYLSULFONYL DERIVATIVE AS ACTIVE INGREDIENT
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Page/Page column 40, (2011/02/15)
[Problem] To provide compounds useful as preventives or remedies for circular system disorders, nervous system disorders, metabolic disorders, reproduction system disorders, digestive system disorders, neoplasm, infectious diseases, etc., or as herbicides. [Means for Solution] A long-chain fatty acyl elongase inhibitor comprising, as the active ingredient thereof, a compound or a pharmaceutically-active salt thereof of a formula (I): [wherein W represents a hydrogen atom, a C1-6 alkyl, etc.; X represents an aryl, a heteroaryl, etc.; n indicates 0 or 1; Z represents a hydrogen atom, a C1-6 alkyl, etc.; A1, A2, A3 and A4 each independently represent CH or N].
