Results 11 to 20 of about 57,923 (191)
Intramolecular Azide to Alkene Cycloadditions for the Construction of Pyrrolobenzodiazepines and Azetidino-Benzodiazepines [PDF]
The coupling of proline- and azetidinone-substituted alkenes to 2-azidobenzoic and 2-azidobenzenesulfonic acid gives precursors that undergo intramolecular azide to alkene 1,3-dipolar cycloadditions to give imine-, triazoline- or aziridine-containing ...
Karl Hemming +3 more
doaj +2 more sources
Intramolecular cycloadditions with high regio- and stereocontrol are important methods for the efficient assembly of complex molecular structures. Efficient routes to the synthesis of norbornadiene-tethered nitrile oxides have been developed, and their ...
Robert Jordan (346146) +3 more
core +18 more sources
Intermolecular 1,3-dipolar cycloadditions of azomethine imines [PDF]
Dipolar cycloadditions of azomethine imines, formed in situ from aldehydes and N1-alkyl-N2-acylhydrazines, with electron-deficient dipolarophiles produce pyrazolidines: mono-substituted dipolarophiles afford principally 4-substituted ...
Raymond C. F. Jones +2 more
doaj +2 more sources
Sydnone-Based Approach to Heterohelicenes through 1,3-Dipolar-Cycloadditions. [PDF]
International audienceThe first approach to pyrazole containing helicenes via sydnone-aryne [3+2]-cycloaddition is described. An unprecedented regioselectivity in the cycloaddition step towards the more sterically constrained product was observed in ...
Yen-Pon E +10 more
europepmc +2 more sources
Intermolecular 1,3-dipolar cycloadditions of azomethine imines [PDF]
Dipolar cycloadditions of azomethine imines, formed in situ from aldehydes and N1-alkyl-N2- acylhydrazines, with electron-deficient dipolarophiles produce pyrazolidines: mono-substituted dipolarophiles afford principally 4-substituted ...
Ray Jones (1249197) +2 more
core +6 more sources
Studies on the [2+3] cycloaddition reaction of nitrile oxides to abietic acid esters [PDF]
[2+3] Dipolar cycloadditions of aromatic nitrile oxides to abietic acid esters were investigated. The reactions showed complete site selectivity and regioselectivity, while the stereoselectivity depended on the structures of the dipolarophiles.
Gucma Mirosław +3 more
doaj +1 more source
Photo-Triggered, Fast, and Fluorogenic Thiophene-Based Cycloalkynes for the Bioorthogonal Fluorescent Labeling of 1,3-Dipole-Tagged Molecules in No-Wash Conditions. [PDF]
Thiophene is king! The fusion of thiophene rings to cycloalkynes super‐charged their copper‐free click chemistry applications, by (1) enhancing the alkyne reactivity (fastest cyclooctyne to date) and (2) rendering the alkyne fluorogenic (with fluorescence enhancement up to 150‐fold upon reaction), making these bioorthogonal reagents ideal for tracking ...
Schulz J +7 more
europepmc +3 more sources
Kinetic solvent effects on 1,3-dipolar cycloadditions of benzonitrile oxide [PDF]
The kinetics of 1,3-dipolar cycloadditions of benzonitrile oxide with a series of N-substituted maleimides and with cyclopentene are reported for water, a wide range of organic solvents and binary solvent mixtures.
Jan B. F. N. Engberts +5 more
core +2 more sources
Cycloadditions with 2-Chloro-1-Nitroethylene
2-chloronitroethylene replaces successfully the still elusive unsubstituted nitroacetylene in both the 1,3-dipolar and Diels-Alder cycloadditions. These reactions generally afford interesting nitrated cyclic and heterocyclic compounds.
R. Verbruggen, H.G. Viehe
doaj +1 more source
The ZnBr2 complex of the title compound has been studied by both structural and theoretical methods. Similar reactivities have been observed for the nitrone alone and the complex in 1,3-dipolar cycloadditions and nucleophilic additions.
Tomas Tejero +5 more
doaj +1 more source

