U.S. Department of Health & Human Services Divider Arrow National Institutes of Health Divider Arrow NCATS

Details

Stereochemistry ACHIRAL
Molecular Formula C4H4
Molecular Weight 52.0746
Optical Activity NONE
Defined Stereocenters 0 / 0
E/Z Centers 0
Charge 0

SHOW SMILES / InChI
Structure of CYCLOBUTADIENE

SMILES

C1=CC=C1

InChI

InChIKey=HWEQKSVYKBUIIK-UHFFFAOYSA-N
InChI=1S/C4H4/c1-2-4-3-1/h1-4H

HIDE SMILES / InChI

Molecular Formula C4H4
Molecular Weight 52.0746
Charge 0
Count
Stereochemistry ACHIRAL
Additional Stereochemistry No
Defined Stereocenters 0 / 0
E/Z Centers 0
Optical Activity NONE

Approval Year

PubMed

PubMed

TitleDatePubMed
Local control of multidimensional dynamics.
2010-12-28
Difluorobenzocyclooctyne: synthesis, reactivity, and stabilization by beta-cyclodextrin.
2010-08-25
Synthesis and reactions of ethynylferrocene-derived fluoro- and chlorocyclotriphosphazenes.
2010-06-21
Effects of cyano substituents on cyclobutadiene and its isomers.
2010-06-10
Second-order state-specific multireference Møller-Plesset perturbation theory (SS-MRMPPT) applied to geometry optimization.
2010-03-18
Structural characterization of (C(2)H(2))(1-6) (+) cluster ions by vibrational predissociation spectroscopy.
2009-09-21
Accounting for the exact degeneracy and quasidegeneracy in the automerization of cyclobutadiene via multireference coupled-cluster methods.
2009-09-21
The quinones of benzocyclobutadiene: a computational study.
2009-08-27
Bis[1,3(η)-all-yl][μ-2(η)-1,3-bis-(di-phenyl-phosphino)-2,4-diphenyl-cyclo-buta-1,3-diene-1:3κP:P']dichlorido-1κCl,3κCl-[2(η)-isopropyl-cyclo-penta-dien-yl]-2-cobalt(I)-1,3-dipalladium(II) dichloro-methane solvate.
2009-05-20
Configuration-driven unitary group approach for generalized Van Vleck variant multireference perturbation theory.
2009-04-23
Computational investigation of hydrogen adsorption by alkali-metal-doped organic molecules: role of aromaticity.
2009-02-02
Direct evaluation of cyclic contributions to the pi energy of conjugated hydrocarbons from strongly localized zero-order pictures.
2008-12-18
Aromaticity and antiaromaticity in 4-, 6-, 8-, and 10-membered conjugated hydrocarbon rings.
2008-12-18
Aromaticity and antiaromaticity in the low-lying electronic states of cyclooctatetraene.
2008-12-11
Performance of block correlated coupled cluster method with the CASSCF reference function for the prediction of activation barriers, spectroscopic constants in diatomic molecules, and singlet-triplet gaps in diradicals.
2008-12-04
A noniterative perturbative triples correction for the spin-flipping and spin-conserving equation-of-motion coupled-cluster methods with single and double substitutions.
2008-11-21
Application of double ionization state-specific equation of motion coupled cluster method to organic diradicals.
2008-11-20
Multireference state-specific Mukherjee's coupled cluster method with noniterative triexcitations.
2008-11-14
Nonperturbative ab initio calculations in strong magnetic fields using London orbitals.
2008-10-21
Unique interactions between diborane and pi orbitals: blue- or red-shifted hydrogen bonding?
2008-09-04
Ground- and excited-state aromaticity and antiaromaticity in benzene and cyclobutadiene.
2008-08-07
Cyclic polyenes of heavy group 14 elements: new generation ligands for transition-metal complexes.
2008-08
Multiconfiguration optimized effective potential method for a density-functional treatment of static correlation.
2008-04-14
Infrared photodissociation spectroscopy of protonated acetylene and its clusters.
2008-03-06
A cheap metal for a "noble" task: preparative and mechanistic aspects of cycloisomerization and cycloaddition reactions catalyzed by low-valent iron complexes.
2008-02-13
Non-resonance-assisted hydrogen bonding in hydroxymethylene and aminomethylene cyclobutanones and cyclobutenones and their nitrogen counterparts.
2007-09-17
Combining two-body density correlation functionals with multiconfigurational wave functions using natural orbitals and occupation numbers.
2007-09-14
On the sigma,pi-energy separation of the aromatic stabilization energy of cyclobutadiene.
2007-05-28
A quantitative scale for the degree of aromaticity and antiaromaticity: a comparison of theoretical and experimental enthalpies of hydrogenation.
2007-02-15
Sigma and pi contributions to the induced magnetic field: indicators for the mobility of electrons in molecules.
2007-01-15
Aromaticity: molecular-orbital picture of an intuitive concept.
2007
Intramolecular reactions in pseudo-geminally substituted [2.2]paracyclophanes.
2007
Cycloalkane and cycloalkene C-H bond dissociation energies.
2006-12-27
Exploration of the potential energy surface of C4H4 for rearrangement and decomposition reactions of vinylacetylene: a computational study. Part I.
2006-12-07
Calculation of electron affinities of polycyclic aromatic hydrocarbons and solvation energies of their radical anion.
2006-11-30
Aromatic superclusters from all-metal aromatic and antiaromatic monomers, [Al4]2- and [Al4]4-.
2006-10-19
Cyclobutadiene: the antiaromatic paradigm?
2006-10-13
Ab initio/Rice-Ramsperger-Kassel-Marcus study of the singlet C4H4 potential energy surface and of the reactions of C2(X1 Sigmag+) with C4H4(X1A1g) and C(1D) with C3H4 (allene and methylacetylene).
2006-10-07
Automerization reaction of cyclobutadiene and its barrier height: an ab initio benchmark multireference average-quadratic coupled cluster study.
2006-08-14
The heat of formation of cyclobutadiene.
2006-07-24
Multireference Brillouin-Wigner coupled clusters method with noniterative perturbative connected triples.
2006-04-14
An energetic measure of aromaticity and antiaromaticity based on the Pauling-Wheland resonance energies.
2006-02-20
Acetylene cyclotrimerization by early second-row transition metals in the gas phase. A theoretical study.
2005-12-26
Lewis acid-mediated generation of bicyclo[5.3.0]decanes and bicyclo[4.3.0]nonanes.
2005-12-22
Properties of a mixed-valence (Fe(II))2(Fe(III))2 square cell for utilization in the quantum cellular automata paradigm for molecular electronics.
2005-12-21
Experimental determination of the heat of hydrogenation of phenylcyclobutadiene.
2005-09-21
An artificial siderophore for the detection of iron(III).
2005-07-21
Tetrasilacyclobutadiene ((t)Bu(2)MeSi)(4)Si(4): a new ligand for transition-metal complexes.
2005-04-27
Ruthenium-catalyzed synthesis of alkylidenecyclobutenes via head-to-head dimerization of propargylic alcohols and cyclobutadiene-ruthenium intermediates.
2005-02-04
Single-electron entrapment of [8]annulyne, biannulenylenes, and an annulenoannulene.
2003-09-17
Substance Class Chemical
Created
by admin
on Mon Mar 31 20:32:43 GMT 2025
Edited
by admin
on Mon Mar 31 20:32:43 GMT 2025
Record UNII
I5G5583N4F
Record Status Validated (UNII)
Record Version
  • Download
Name Type Language
ANNULENE
Preferred Name English
CYCLOBUTADIENE
MI  
Systematic Name English
CYCLOBUTADIENE [MI]
Common Name English
1,3-CYCLOBUTADIENE
Systematic Name English
Code System Code Type Description
CAS
1120-53-2
Created by admin on Mon Mar 31 20:32:43 GMT 2025 , Edited by admin on Mon Mar 31 20:32:43 GMT 2025
PRIMARY
FDA UNII
I5G5583N4F
Created by admin on Mon Mar 31 20:32:43 GMT 2025 , Edited by admin on Mon Mar 31 20:32:43 GMT 2025
PRIMARY
CHEBI
33657
Created by admin on Mon Mar 31 20:32:43 GMT 2025 , Edited by admin on Mon Mar 31 20:32:43 GMT 2025
PRIMARY
MERCK INDEX
m3977
Created by admin on Mon Mar 31 20:32:43 GMT 2025 , Edited by admin on Mon Mar 31 20:32:43 GMT 2025
PRIMARY Merck Index
EPA CompTox
DTXSID00149807
Created by admin on Mon Mar 31 20:32:43 GMT 2025 , Edited by admin on Mon Mar 31 20:32:43 GMT 2025
PRIMARY
WIKIPEDIA
Cyclobutadiene
Created by admin on Mon Mar 31 20:32:43 GMT 2025 , Edited by admin on Mon Mar 31 20:32:43 GMT 2025
PRIMARY
CHEBI
33662
Created by admin on Mon Mar 31 20:32:43 GMT 2025 , Edited by admin on Mon Mar 31 20:32:43 GMT 2025
PRIMARY
PUBCHEM
136879
Created by admin on Mon Mar 31 20:32:43 GMT 2025 , Edited by admin on Mon Mar 31 20:32:43 GMT 2025
PRIMARY