Results 11 to 20 of about 22,823 (226)

Halogen-Bond Mediated [2+2] Photodimerizations: À la Carte Access to Unsymmetrical Cyclobutanes in the Solid State

Molecules, 2022
The ditopic halogen-bond (X-bond) donors 1,2-, 1,3-, and 1,4-diiodotetrafluorobenzene (1,2-, 1,3-, and 1,4-di-I-tFb, respectively) form binary cocrystals with the unsymmetrical ditopic X-bond acceptor trans-1-(2-pyridyl)-2-(4-pyridyl)ethylene (2,4-bpe ...
Jay Quentin, Eric W. Reinheimer, Leonard R. MacGillivray   +2 more
doaj   +1 more source

The Synthesis and Acid-base Properties of α-(Fluoromethyl)- and α-(Difluoromethyl)-substituted Cyclobutane Building Blocks

Журнал органічної та фармацевтичної хімії, 2023
Aim. To synthesize cyclobutane-derived amines and carboxylic acids bearing CH2F or CHF2 groups in the α position; to determine the regularities of the effect of fluoroalkyl substituents on the acid-base properties of the title compounds.
Oleksandr Demchuk, Oleksandr Grygorenko
doaj   +1 more source

Supramolecular Sandwiches: Halogen-Bonded Coformers Direct [2+2] Photoreactivity in Two-Component Cocrystals

Molecules, 2020
The halogen-bond (X-bond) donors 1,3- and 1,4-diiodotetrafluorobenzene (1,3-di-I-tFb and 1,4-di-I-tFb, respectively) form cocrystals with trans-1,2-bis(2-pyridyl)ethylene (2,2′-bpe) assembled by N···I X-bonds.
Jay Quentin, Dale C. Swenson, Leonard R. MacGillivray   +2 more
doaj   +1 more source

Halogen-bonded zigzag molecular network based upon 1,2-diiodoperchlorobenzene and the photoproduct rctt-1,3-bis(pyridin-4-yl)-2,4-diphenylcyclobutane

Acta Crystallographica Section E: Crystallographic Communications, 2022
The formation and crystal structure of a zigzag molecular network held together by I...N halogen bonds is reported. In particular, the halogen-bond donor is 1,2-diiodoperchlorobenzene (1,2-C6I2Cl4) while the acceptor is a head-to-tail photoproduct ...
Taylor J. Dunning, Eric Bosch, Ryan H. Groeneman   +2 more
doaj   +1 more source

Synthesis of novel β-aminocyclobutanecarboxylic acid derivatives by a solvent-free aza-Michael addition and subsequent ring closure [PDF]

, 2011
Novel beta-aminocyclobutanecarboxylic acid derivatives were prepared via a sequential solvent-free aza-Michael addition of benzophenone imine across 3-halopropylidenemalonates and base-induced ring closure.
Aitken, Appella, Brannock, Caine, Choudhary, Declerck, Fernandes, Fernandes, Fernandes, Frackenpohl, Fülöp, Fülöp, Gademann, Gauzy, Gauzy, Gellman, Gorrea, Hall, Imanzadeh, Izquierdo, Kiss, Krapcho, Kuhl, Lehnert, Liu, Mangelinckx, Mangelinckx, Mangelinckx, Mangelinckx, Martinek, Martín-Vilà, Mittendorf, Norbert De Kimpe, Oki, Palko, Rúa, Seebach, Seebach, Su, Sulmon, Sven Mangelinckx, Tamara Meiresonne, Torres, Trabocchi, White   +44 more
core   +1 more source

3-(2,6-Dioxopiperidin-3-yl)-3-azabicyclo[3.2.0]heptane-2,4-dione

Acta Crystallographica Section E, 2009
The title molecule, C11H12N2O4, consists of a 3-azabicyclo[3.2.0]heptane group containing a nearly planar cyclobutane ring (r.m.s. deviation of fitted atoms is 0.0609 Å), fused to a pyrrolidine ring, bonded to a 2,6-dioxopiperidine ring at the
Jerry P. Jasinski, Ray J. Butcher, Earl Benjamin, Ellis Benjamin, Yousef M. Hijji   +4 more
doaj   +1 more source

Photochemical Approaches to Complex Chemotypes: Applications in Natural Product Synthesis. [PDF]

, 2016
The use of photochemical transformations is a powerful strategy that allows for the formation of a high degree of molecular complexity from relatively simple building blocks in a single step. A central feature of all light-promoted transformations is the
Kärkäs, Markus D., Porco, John A., Stephenson, Corey R.J.   +2 more
core   +2 more sources

Cycloaddition Chemistry of a Silylene‐Nickel Complex toward Organic π‐Systems: From Reversibility to C−H Activation [PDF]

, 2020
The versatile cycloaddition chemistry of the Si−Ni multiple bond in the acyclic (amido)(chloro)silylene→Ni0 complex 1, [(TMSL)ClSi→Ni(NHC)2] (TMSL=N(SiMe3)Dipp; Dipp=2,6‐iPr2C6H4; NHC=C[(iPr)NC(Me)]2), toward unsaturated organic substrates is reported ...
Drieß, Matthias, Hadlington, Terrance J., Kostenko, Arseni   +2 more
core   +1 more source

Stereocontrolled Synthesis and Functionalization of Cyclobutanes and Cyclobutanones

Molecules, 2013
In the last decade a certain number of new cyclobutane and cyclobutanone synthesis and functionalization protocols have been published. Organo- and biocatalyzed eco-friendly approaches to cyclobutane-containing molecules have been developed with ...
Francesco Secci, Angelo Frongia, Pier Paolo Piras   +2 more
doaj   +1 more source

Generalized valence bond wave functions in quantum Monte Carlo [PDF]

, 2010
We present a technique for using quantum Monte Carlo (QMC) to obtain high quality energy differences. We use generalized valence bond (GVB) wave functions, for an intuitive approach to capturing the important sources of static correlation, without ...
Anderson, Amos G., Goddard, William A., III   +1 more
core   +1 more source