- Inverse demand [4+2] cycloaddition reactions of allenamides: Reactivity scopes of an electron deficient variant of allenamines
-
The synthesis and reactivity of a series of new allenamides are described. These electron deficient variants of allenamines are more stable than allenamines but possess comparable reactivity. Particularly, oxazolidinone and imidazolidinone substituted allenamides undergo efficient inverse demand [4+2] cycloaddition reactions with heterodienes, leading to unique pyranyl heterocycles. The reactivity differences between various allenamides containing different substitution patterns around the nitrogen atom are illustrated.
- Wei, Lin-Li,Xiong, Hui,Douglas, Christopher J.,Hsung, Richard P.
-
-
Read Online
- Au(I)-Catalyzed Synthesis of Trisubstituted Indolizines from 2-Propargyloxypyridines and Methyl Ketones
-
A new Au(I)-catalyzed method for the preparation of trisubstituted indolizines from easily accessible 2-propargyloxy-pyridines is reported. The reaction tolerates a wide range of functionality, allowing for diversity to be introduced in four distinct regions of the product (R, R1, R2, and Ar). The proposed mechanism proceeds via enol addition to an allenamide intermediate and explains the observed increase in yields when electron poor methyl ketones are utilized.
- Rossler, Matthew D.,Hartgerink, Colin T.,Zerull, Emily E.,Boss, Benjamin L.,Frndak, Abigail K.,Mason, Miles M.,Nickerson, Leslie A.,Romero, Evan O.,Van De Burg, Jaimie E.,Staples, Richard J.,Anderson, Carolyn E.
-
supporting information
p. 5591 - 5595
(2019/08/01)
-
- Nickel-catalyzed synthesis of stereochemically defined enamides via Bi- and tricomponent coupling reaction
-
The stereoselective synthesis of (E)-trisubstituted tertiary enamides is documented via site-selective Ni-catalyzed β-arylation of allenamides with boronic acids in high yields (up to 89%). The nucleophilic character of the "organo-Ni" intermediates is further exploited to implement a one-pot tricomponent procedure involving the final allylation of aldehydes (yields up to 93%). Mechanistic insights and efficiency on a gram scale process were also documented.
- Liu,De Nisi,Cerveri,Monari,Bandini
-
supporting information
p. 5034 - 5037
(2017/11/06)
-
- A simple one-pot preparation of N-allenyl amides, ureas, carbamates and sulfonamides using a DMSO/tBuOK protocol
-
A one-pot transformation of amides, ureas, carbamates and sulfonamides into synthetically useful N-allenyl analogues using a tBuOK/DMSO protocol is reported. The procedure is experimentally simple and robust, and provides N-allenyl analogues, c
- Bousfield, Thomas W.,Kimber, Marc C.
-
p. 350 - 352
(2015/03/18)
-
- On the base-induced isomerization of cyclic propargylamides to cyclic allenamides
-
The reaction of lactams 4 (n = 1-5) with propargyl bromide affords propargylamides or allenylamides depending on the ring-size. Theoretical calculations support the dependence of the extension of the isomerization on the ring-size.
- Fenández, Israel,Monterde, María I.,Plumet, Joaquín
-
p. 6029 - 6031
(2007/10/03)
-
- Efficient preparations of novel ynamides and allenamides
-
Practical syntheses of a series of novel ynamides and allenamides are described here. While a base-induced isomerization protocol of propargyl amides leads to an array of chiral and achiral allenamides, ynamides are prepared from enamides via bromination followed by base-induced elimination of the Z-bromoenamides. These ynamides and allenamides possess improved thermal stability compared to ynamines and allenamines. They can be isolated, purified, and handled with ease, and thus, should be synthetically more useful than traditional ynamines and allenamines.
- Wei, Lin-Li,Mulder, Jason A.,Xiong, Hui,Zificsak, Craig A.,Douglas, Christopher J.,Hsung, Richard P.
-
p. 459 - 466
(2007/10/03)
-