Molecular Structure of Chromocene (CAS NO.1271-24-5):

IUPAC Name: Chromium(2+); cyclopenta-1,3-diene 
Molecular Formula: C₁₀H₁₀Cr
Molecular Weight: 182.18
EINECS: 215-036-4 
Density: 1.43 g/cm³, solid
Melting point: 168-170 °C
Melting Point: 168-170 °C(lit.)
Enthalpy of Vaporization: 27.4 kJ/mol
Boiling Point: 41.5 °C at 760 mmHg
Vapour Pressure: 418 mmHg at 25 °C
Sensitive: Air & Moisture Sensitive
Classification Code: Mutation data 
Product Categories: Organometallics 
Solubility in water: decomposes in water
Appearance: Red needles or reddish-purple solid.
Canonical SMILES: [CH-]1C=CC=C1.[CH-]1C=CC=C1.[Cr+2]
InChI: InChI=1S/2C5H5.Cr/c2*1-2-4-5-3-1;/h2*1-5H;/q2*-1;+2
InChIKey: TYYBBNOTQFVVKN-UHFFFAOYSA-N

 Chromocene (CAS NO.1271-24-5) is prepared by the following route:
 CrCl₂ + 2 NaC₅H₅ → Cr(C₅H₅)₂ + 2 NaCl

Safety Information of Chromocene (CAS NO.1271-24-5):
Hazard Codes:Xn,Xi
Risk Statements: 20/21/22-36/37/38 
R20/21/22:Harmful by inhalation, in contact with skin and if swallowed. 
R36/37/38:Irritating to eyes, respiratory system and skin.
Safety Statements: 26-37/39 
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. 
S37/39:Wear suitable gloves and eye/face protection.
RIDADR: 1325
WGK Germany: 3
RTECS: GB7600000
HazardClass: 4.2
PackingGroup: I

 Chromocene (CAS NO.1271-24-5), its Synonyms are Bis(cyclopentadiene)chromium ; Bis(cyclopentadiene)chromium(II) ; Bis(cyclopentadienyl)chromium ; Bis(cyclopentadienyl)chromium(II) ; CCRIS 5974 ; Chromium, dicyclopentadienyl- ; Di((eta-5)-cyclopentadienyl)chromium ; Dicyclopentadienylchromium ; Bis(eta5-cyclopenta-2,4-dien-1-yl)chromium . It is very sensitive to exposure to air and moisture (decomposition is not vigorous). 
 Chromocene reacts with water and alcohols. . It's reaction with alcohols produces pyrophoric metal alkoxides (dialkoxychromium and cyclopentadiene).It is often abbreviated Cp₂Cr. This sandwich compound is structurally similar to ferrocene but does not follow the 18-electron rule because it only has 16 electrons and therefore it also paramagnetic and far more reactive.