Chemoselective synthesis of highly substituted 1,2-allenyl ketones, furans, and 2-alkynyl ketones from reaction of lithium selenolates with 1-(1-alkynyl)cyclopropyl ketones and electrophiles.
نویسندگان
چکیده
A homo-Michael addition reaction of lithium selenolates with 1-(1-alkynyl)cyclopropyl ketones and the subsequent reaction with electrophiles such as PhSeBr, NFSI and NCS is reported. Based on the nature of electrophiles, this reaction may afford highly substituted 1,2-allenyl ketones or furans (E(+) = PhSe(+)) and 2-alkynyl ketones (E(+) = F(+), Cl(+), active halides) as the final products, respectively.
منابع مشابه
A DFT study on the mechanism of gold(III)-catalyzed synthesis of highly substituted furans via [3, 3]-sigmatropic rearrangements and/or [1, 2]-acyloxy migration based on propargyl ketones.
The mechanisms of gold(III)-catalyzed synthesis of highly substituted furans via [3,3]-sigmatropic rearrangements and/or [1,2]-acyloxy migration based on propargyl ketones have been investigated using density functional theory calculations at BHandHLYP/6-31G(d,p) (SDD for Au) level of theory. Solvent effects on these reactions were explored using calculations that included a polarizable continu...
متن کاملKinetic resolution of 1-(1-alkynyl)cyclopropyl ketones by gold(I)-catalyzed asymmetric [4+3]cycloaddition with nitrones: scope, mechanism and applications.
Highly useful optically active 1-(1-alkynyl)cyclopropyl ketones can be efficiently obtained by the kinetic resolution of the easily available racemic ones under the catalysis of the chiral gold(I) species. Reaction scope and synthetic applications are also investigated.
متن کاملSynthesis of Polycyclic Ring Systems Using Transition Metal Catalyzed Cyclizations of Diazo Alkynyl Ketones
Abstract: The rhodium(II)-catalyzed reaction of α-diazo ketones bearing tethered alkyne units represents a new and useful method for the construction of a variety of substituted cyclopentenones. The process proceeds by addition of the rhodium-stabilized carbenoid onto the acetylenic π-bond to give a vinyl carbenoid intermediate. The resulting rhodium complex undergoes a wide assortment of react...
متن کامل[3,3]-Sigmatropic rearrangement/5-exo-dig cyclization reactions of benzyl alkynyl ethers: synthesis of substituted 2-indanones and indenes.
Substituted benzyl alkynyl ethers, prepared from the corresponding α-alkoxy ketones in a two-step sequence involving enol triflate formation and KOtBu-induced E2 elimination, undergo [3,3]-sigmatropic rearrangement/intramolecular 5-exo-dig cyclization at 60 °C to form substituted 2-indanones in good overall yields. 1,3-cis-Disubstituted-2-indanones are formed preferentially when the benzylic su...
متن کاملManganese η2-complexes as auxiliaries for stereoselective aldol synthesis of allenyl carbinols.
A convenient and robust manganese auxiliary was linked via an η(2)-bond to alkynyl esters and ketones using a mild complexation reaction with methylcyclopentadienyl manganese tricarbonyl. This complex readily underwent aldol reactions with exclusive α-substitution and in good diastereoselectivities especially with aryl ketone substrates. This selectivity has been rationalized using a cyclic tra...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Organic & biomolecular chemistry
دوره 10 18 شماره
صفحات -
تاریخ انتشار 2012