ISSN:
0009-2940
Keywords:
1,3-Cyclopentadiene-5-carbonyl chloride, 1,2,3,4,5-pentamethyl-
;
1,3-Cyclopentadiene-5-carbothioyl chloride, 1,2,3,4,5-pentamethyl-
;
Ketone, bis(1,2,3,4,5-pentamethyl-1,3-cyclopentadien-5-yl)
;
Thioketone, bis(1,2,3,4,5-pentamethyl-1,3-cyclopentadien-5-yl)
;
Diels-Alder preformation
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Bis(pentamethylcyclopentadienyl) Ketone and Thioketone: Carbon Compounds with Performed Diels-Alder Geometry1,2,3,4,5-Pentamethyl-1,3-cyclopentadien-5-carbonyl chloride (2) is formed in good yields by the reaction of pentamethylcyclopentadienyllithium (1) with phosgene. The corresponding carbothioyl chloride 3 is synthesized by treatment of 1 with thiophosgene. Both acyl chlorides are stable against air and moisture and difficult to attack in SN2-type reactions. Treatment of 2 and 3 with trimethyl(pentamethylcyclopentadienyl)stannane in the presence of boron trifluoride - ether leads to bis(1,2,3,4,5-pentamethyl-1,3-cyclopentadien-5-yl) ketone (5) and thioketone (6), respectively. Even at room temperature, 5 and 6 tend to intramolecular [4 + 2] cycloaddition reactions. X-ray crystal structure investigations of 2, 5, and 6 show the steric demand of the pentamethylcyclopentadienyl ligand and explain the untypical chemical behavior of 2 and the easy [2 + 4] cycloaddition reactions of 5 and 6.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19931260219
