Bis(cyclopentadienyl)titanium dichloride

• Catalog No.: A11456
• CAS Number: 1271-19-8
• M. F.: C10H10Cl2Ti
• M. W.: 248.9594
• Purity: 97%

SYNONYMS

• Title: 双(环戊二烯)二氯化钛
• IUPAC name: bis(cyclopenta-2,4-dien-1-yl)titaniumbis(ylium) dichloride
• IUPAC Traditional name: bis(cyclopenta-2,4-dien-1-yl)titaniumbis(ylium) dichloride
• Synonyms: Titanocene dichloride; Dichlorobis(cyclopentadienyl)titanium

DATABASE IDS

• MDL Number: MFCD00003723
• EC Number: 215-035-9
• CAS Number: 1271-19-8
• Merck Index: 149482

PROPERTIES

• Purity: 97%
• Density: 1.60
• Melting Point: ca 285°C dec.
• Solubility: Slightly soluble in water
• GHS Hazard statements: H301-H332-H315-H335-H318-H341
• European Hazard Symbols: X
• GHS Precautionary statements: P261-P301+P310-P305+P351+P338-P302+P352-P405-P501A
• Risk Statements: 20/22-37/38-41-68
• RTECS: XR2050000
• Safety Statements: 9-26-36/37/39
• Storage Warning: Air & Moisture Sensitive
• TSCA Listed: 是

REFERENCES

• In combination with trimethyaluminum, generates an ylide (Tebbe reagent): J. Am. Chem. Soc., 100, 3611 (1978), which transfers a methylene group not only to aldehydes and ketones (cf Wittig reaction) but also to the carbonyl groups of esters and lactones: J. Am. Chem. Soc., 102, 3270 (1980):
  
• A similar reagent can be prepared by reaction with the Simmons-Smith adduct (see Diiodomethane, A15457) and used for the methylenation of ketones in excellent yields: Tetrahedron Lett., 24, 2043 (1983).
• Reacts with Grignard reagents with a ?-hydrogen atom (e.g. isobutyl or isopropyl) to form, in a catalytic cycle, a titanium hydride species, which reduces aldehydes, ketones and esters to alcohols: Tetrahedron Lett., 21, 2171, 2175 (1980). The same combination effects regioselective cis-hydromagnesation of alkynes to give alkenyl Grignard reagents: Tetrahedron Lett., 22, 85 (1981); J. Chem. Soc., Chem. Commun., 718 (1981). For application in a highly stereospecific synthesis of vinylsilanes in excellent yields, see: Tetrahedron Lett., 24, 1041 (1983):
  
• For further examples of the hydroxymagnesation of alkynes, see: Org. Synth. Coll., 8, 507 (1993). Similarly π-allyl complexes with 1,3-dienes can be generated, which react regio-and stereo-selectively with aldehydes to give homoallylic alcohols: J. Chem. Soc., Chem. Commun., 621 (1984):
  
• For use, in combination with Mg metal, in formation of titanocycle intermediates, see: J. Org. Chem., 63, 9285 (1998); for reaction scheme, see Triphosgene, A14932.