An efficient coupling of terminal alkynes and CO(2) in the presence of alkyl halides can be achieved under ambient conditions using a copper/phosphine catalyst system, providing facile access to a variety of functionalised alkyl 2-alkynoates.
In this study, a facile synthesis of 3-carboxylated indoles involving a tandem-type cyclization of 2-ethynylanilines and subsequent CO2 fixation at the 3-position of the indole ring is realized. The reaction proceeds efficiently at 65 °C under 10 atm of CO2, giving rise to variously substituted 3-carboxylated indoles, generally in high yields. An inorganic base, such as K2CO3, is the only reagent required, and the addition of transition metal catalysts is not necessary. The method provides a novel, simple, and promising strategy for CO2 fixation in the research field of heterocyclic chemistry.
Nanofibrous nonwoven
fabrics have attracted attention as porous
adsorbents with high specific surface areas for the safe and efficient
treatment of spilled organic dyes and petroleum. For this purpose,
a method of fabricating porous nanofibers with high specific surface
areas would be highly beneficial. In this study, the phase separation
in nanofibers electrospun from blended solutions of immiscible polymers
[poly(styrene) (PS) and poly(vinylpyrrolidone) (PVP)] was investigated.
The removal of PVP as a sacrificial polymer afforded the imprinting
of mesopores (40–70 nm) in the PS nanofibers. The effects of
solution composition (PS/PVP in
N
,
N
-dimethylformamide) on the structure formation in the fibers were
investigated. The nanofibers thus obtained could selectively adsorb
low-molecular-weight hydrophobic dyes, such as Nile Red and Oil Red
O. Thus, it is expected that the combined approach of electrospinning
of immiscible polymer blends and phase separation-induced patterning
can be applied to the fabrication of functional nanofibers for diverse
applications.
The hydroxymethylation of alkynylsilanes with formaldehyde generated in situ from N‐[(trimethylsiloxy)methyl]phthalimide proceeds in the presence of a stoichiometric amount of NaOPh. The reaction occurs at room temperature by using an operationally simple one‐step procedure. A variety of alkynylsilanes possessing electron‐donating, electron‐withdrawing, and halogen groups (including heteroaryl‐substituted alkynylsilanes) provide hydroxymethylated products.
Under ambient conditions, aromatic, heteroaromatic, and aliphatic alkynes undergo the CuI/PEt3 catalyzed carboxylation with CO2 and alkyl bromides or iodides to give the title esters.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.