1 Methyl 1 3 Cyclopentadiene

Methylcyclopentadiene
Names
Left to right: 2-methyl-ane,iii-cyclopentadiene; 1-methyl-i,3-cyclopentadiene; 5-methyl-one,3-cyclopentadiene
Other names Cp′; MeCp
Identifiers
CAS Number	unspec: 96-38-8 ^N i-methyl: 96-39-9 ^N 2-methyl: 3727-31-nine ^N 5-methyl: 26519-91-v ^N
3D model (JSmol)	one-methyl: Interactive image ii-methyl: Interactive epitome 5-methyl: Interactive image
ChemSpider	one-methyl: 60141 2-methyl: 121669 5-methyl: 23802
ECHA InfoCard	100.043.400
EC Number	1-methyl: 247-724-5
PubChem CID	i-methyl: 66775 2-methyl: 138026 5-methyl: 25512
UNII	i-methyl: K4O53GR393 five-methyl: X1DWO24VEA
Un number	1993
CompTox Dashboard (EPA)	i-methyl: DTXSID0067216 two-methyl: DTXSID10190729 5-methyl: DTXSID7048035
InChI ane-methyl: InChI=1S/C6H8/c1-vi-4-two-three-5-6/h2-4H,5H2,1H3^Y Key: NFWSQSCIDYBUOU-UHFFFAOYSA-N^Y 2-methyl: InChI=1S/C6H8/c1-six-4-two-iii-v-6/h2,4-5H,3H2,1H3 Key: AHQZRFBZJSCKAV-UHFFFAOYSA-Northward 5-methyl: InChI=1S/C6H8/c1-6-4-two-3-5-6/h2-6H,1H3 Key: QVRBGKYLLCLCHL-UHFFFAOYSA-N
SMILES ane-methyl: C\one=C\C=C(\C)C/one 2-methyl: C\1=C\C(\C)=CC/ane five-methyl: C\ane=C\C=CC/one(\C)
Backdrop
Chemical formula	C ₆ H ₈
Molar mass	80.130 yard·mol⁻¹
Hazards
GHS labelling:
Pictograms
Signal give-and-take	Danger
Hazard statements	H226, H350, H410
Precautionary statements	P201, P202, P210, P233, P240, P241, P242, P243, P273, P280, P281, P303+P361+P353, P308+P313, P370+P378, P391, P403+P235, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Yverify (what is^{Y Due north} ?) Infobox references

Chemical compound

Methylcyclopentadiene is any of iii isomeric circadian dialkenes with the formula C₅MeH₅ (Me = CH₃). These isomers are the organic precursor to the methylcyclopentadienyl ligand (C_fiveH₄Me, often denoted every bit Cp′), commonly found in organometallic chemistry.

Every bit with cyclopentadiene, methylcyclopentadiene is prepared past thermal cracking of its Diels–Alder dimer, followed past distillation for removal of cyclopentadiene, a common impurity.^[ane]

Methylcyclopentadienyl anion [edit]

Structure of Cp′Fe(PPh_three)(CO)I, with labels for the 4 diastereotopic ring protons.

Deprotonation of methylcyclopentadiene gives the aromatic methylcyclopentadienyl anion.^[2] This ion is useful as a ligand for organometallic complexes. Relative to the corresponding cyclopentadienyl (Cp) complexes, complexes of Cp′ exhibit enhanced solubility in organic solvents.

Cp′ tin be used to probe the structure of organometallic complexes. For example, Cp′Atomic number 26(PPh_iii)(CO)I has four different signals in the ^oneH NMR spectrum for the band hydrogens and 5 unlike signals in the ^thirteenC NMR spectrum for the ring carbons. There is therefore no symmetry within the ring even accounting for rotation around the ring–metallic centrality, but instead at that place is a diastereotopic relationship as a consequence of beingness function of a chiral complex. The achiral forerunner complex Cp′Fe(CO)₂I has but two signals for those hydrogens and iii for those carbons, indicating a symmetric structure.^[iii]

References [edit]

^ Darkwa, James; Giolando, Dean M.; Irish potato, Catherine Jones; Rauchfuss, Thomas B. (1990). "Bis(η ⁵-Methylcyclopentadienyl)Titanium Pentasulfide, Bis(η-Methylcyclopentadienyl)-Divanadium Pentasulfide, and Bis(η ⁵-Methylcyclopentadienyl)Divanadium Tetrasulfide". Inorg. Synth. 27: 51. doi:x.1002/9780470132586.ch10.
^ Wilkinson, G. (1956). "Ferrocene". Organic Syntheses. 36: 31. doi:10.15227/orgsyn.036.0031.
^ Carlton, L.; Johnston, P.; Coville, N. J. (1988). "Substituted cyclopentadienyl complexes. II. ¹³C NMR spectra of some [(η ⁵-C₅H₄Me)Fe(CO)(L)I] complexes". J. Organomet. Chem. 339 (iii): 339–343. doi:10.1016/S0022-328X(00)99395-1.