Cyclohexane conformationCyclohexane conformations are any of several three-dimensional shapes adopted by cyclohexane. Because many compounds feature structurally similar six-membered rings, the structure and dynamics of cyclohexane are important prototypes of a wide range of compounds. The internal angles of a regular, flat hexagon are 120°, while the preferred angle between successive bonds in a carbon chain is about 109.5°, the tetrahedral angle (the arc cosine of −1/3).
Strain (chemistry)In chemistry, a molecule experiences strain when its chemical structure undergoes some stress which raises its internal energy in comparison to a strain-free reference compound. The internal energy of a molecule consists of all the energy stored within it. A strained molecule has an additional amount of internal energy which an unstrained molecule does not. This extra internal energy, or strain energy, can be likened to a compressedspring.
Ring flipIn organic chemistry, a ring flip (also known as a ring inversion or ring reversal) is the interconversion of cyclic conformers that have equivalent ring shapes (e.g., from a chair conformer to another chair conformer) that results in the exchange of nonequivalent substituent positions. The overall process generally takes place over several steps, involving coupled rotations about several of the molecule's single bonds, in conjunction with minor deformations of bond angles.
HyperconjugationIn organic chemistry, hyperconjugation (σ-conjugation or no-bond resonance) refers to the delocalization of electrons with the participation of bonds of primarily σ-character. Usually, hyperconjugation involves the interaction of the electrons in a sigma (σ) orbital (e.g. C–H or C–C) with an adjacent unpopulated non-bonding p or antibonding σ* or π* orbitals to give a pair of extended molecular orbitals.
AtropisomerAtropisomers are a kind of stereoisomer arising because of hindered rotation about a single bond, where energy differences due to steric strain or other contributors create a barrier to rotation that is high enough to allow for isolation of individual rotamers. They occur naturally and are of occasional importance in pharmaceutical design.
Potential energy surfaceA potential energy surface (PES) or energy landscape describes the energy of a system, especially a collection of atoms, in terms of certain parameters, normally the positions of the atoms. The surface might define the energy as a function of one or more coordinates; if there is only one coordinate, the surface is called a potential energy curve or energy profile. An example is the Morse/Long-range potential.
CyclohexaneNames Preferred IUPAC nameCyclohexaneOther names Hexanaphthene (archaic)Identifiers CAS Number110-82-73D model (JSmol)Interactive imageBeilstein Reference1900225 ChEBICHEBI:29005ChEMBLChEMBL15980ChemSpider7787DrugBankDB03561ECHA InfoCard100.003.461Gmelin Reference1662 KEGGC11249PubChemCID8078RTECS numberGU6300000UNII48K5MKG32SUN number1145 CompTox Dashboard(EPA)DTXSID4021923InChIInChI=1S/C6H12/c1-2-4-6-5-3-1/h1-6H2Key: XDTMQSROBMDMFD-UHFFFAOYSA-NInChI=1/C6H12/c1-2-4-6-5-3-1/h1-6H2Key: XDTMQSROBMDMFD-UHFFFAOYAZSMILESC1CCCCC1Properties Chemical formulaC6H12Molar mass84.162 g·mol Appearance Colourless liquid OdorSweet, gasoline-like Density0.7739 g/ml (liquid); 0.996 g/ml (solid) Melting point6.47 °C (43.65 °F; 279.62 K) Boiling point80.74 °C (177.33 °F; 353.89 K) Solubility in waterImmiscible SolubilitySoluble in ether, alcohol, acetoneVapor pressure78 mmHg (20 °C) Magnetic susceptibility (χ)−68.13·10 cm/mol Refractive index (nD)1.42662 Viscosity1.02 cP at 17 °C Hazards GHS labelling: PictogramsSignal wordDangerHazard statementsH225, H304, H315, H336Precautionary statementsP210, P233, P240, P241, P242, P243, P261, P264, P271, P273, P280, P301+P310, P302+P352, P303+P361+P353, P304+P340, P312, P321, P331, P332+P313, P362, P370+P378, P391, P403+P233, P403+P235, P405, P501NFPA 704 (fire diamond) 130Flash point−20 °C (−4 °F; 253 K) Autoignitiontemperature245 °C (473 °F; 518 K) Explosive limits1.3–8% Lethal dose or concentration (LD, LC): LD50 (median dose)12705 mg/kg (rat, oral)813 mg/kg (mouse, oral) LCLo (lowest published)17,142 ppm (mouse, 2 h)26,600 ppm (rabbit, 1 h) NIOSH (US health exposure limits): PEL (Permissible)TWA 300 ppm (1050 mg/m) REL (Recommended)TWA 300 ppm (1050 mg/m) IDLH (Immediate danger)1300 ppm Thermochemistry Std enthalpy offormation(ΔfH298)−156 kJ/mol Std enthalpy ofcombustion(ΔcH298)−3920 kJ/mol Related compounds Related cycloalkanesCyclopentaneCycloheptaneRelated compoundsCyclohexeneBenzeneSupplementary data page Cyclohexane (data page)Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).Yverify ( ?)
MoleculeA molecule is a group of two or more atoms that are held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemistry, and biochemistry, the distinction from ions is dropped and molecule is often used when referring to polyatomic ions.
Single bondIn chemistry, a single bond is a chemical bond between two atoms involving two valence electrons. That is, the atoms share one pair of electrons where the bond forms. Therefore, a single bond is a type of covalent bond. When shared, each of the two electrons involved is no longer in the sole possession of the orbital in which it originated. Rather, both of the two electrons spend time in either of the orbitals which overlap in the bonding process.
Drug designDrug design, often referred to as rational drug design or simply rational design, is the inventive process of finding new medications based on the knowledge of a biological target. The drug is most commonly an organicsmall molecule that activates or inhibits the function of a biomolecule such as a protein, which in turn results in a therapeutic benefit to the patient.
AtomAtoms are the basic particles of the chemical elements and the fundamental building blocks of matter. An atom consists of a nucleus of protons and generally neutrons, surrounded by an electromagnetically bound swarm of electrons. The chemical elements are distinguished from each other by the number of protons that are in their atoms. For example, any atom that contains 11 protons is sodium, and any atom that contains 29 protons is copper.
ChemistryScientific study of matter's behavior and propertiesImages relating to the six main branches of chemistry, clockwise from the upper left : a BeF₂ glass network (inorganic chemistry), a caffeine molecule (organic chemistry), a reaction coordinate diagram (physical chemistry), a proton NMR spectrum (analytical chemistry), the RGS4 protein (biochemistry), and a glowstick using chemiluminescence (applied chemistry).Chemistry is the scientific study of the properties and behavior of matter.
Half-lifeHalf-life (symbol t½) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable atoms survive. The term is also used more generally to characterize any type of exponential (or, rarely, non-exponential) decay.
diaxialRelated word or term.*As an Amazon Associate I earn from qualifying purchases.