Lautens, Mark published the artcileCobalt-Catalyzed [2¦Ð + 2¦Ð + 2¦Ð] (Homo-Diels-Alder) and [2¦Ð + 2¦Ð + 4¦Ð] Cycloadditions of Bicyclo[2.2.1]hepta-2,5-dienes, HPLC of Formula: 4141-48-4, the publication is Journal of the American Chemical Society (1995), 117(26), 6863-79, database is CAplus.
The scope of the cobalt-catalyzed [2¦Ð + 2¦Ð + 2¦Ð] (homo-Diels-Alder, HDA) and [2¦Ð + 2¦Ð + 4¦Ð] cycloaddition reactions with norbornadienes has been investigated. Cobalt acetylacetonate, Co(acac)3 or Co(acac)2, upon reduction by diethylaluminum chloride (Et2AlCl) in the presence of 1,2-bis(diphenylphosphino)ethane (dppe), is very effective in promoting the HDA reaction between norbornadiene and a variety of unactivated acetylenes to yield deltacyclenes. Azeotropic drying of the cobalt compound before use is found to increase the reactivity of the catalyst. Moderate to excellent enantioselectivity of these [2¦Ð + 2¦Ð + 2¦Ð] (up to 91% ee) and [2¦Ð + 2¦Ð + 4¦Ð] (up to 79% ee) cycloadditions can be achieved by the use of a chiral phosphine. 7-Substituted norbornadienes are also found to be reactive in the cobalt-catalyzed HDA reactions, affording the corresponding deltacyclenes in good yields. However, low anti/syn selectivities are observed, in contrast with the corresponding nickel-catalyzed HDA reaction with electron-deficient dienophiles. 2-Substituted norbornadienes are found to be less reactive in the cobalt-catalyzed HDA reactions, and the regio- and stereoselectivities are only moderate. The intramol. versions of these [2¦Ð + 2¦Ð + 2¦Ð] and [2¦Ð + 2¦Ð + 4¦Ð] cycloadditions have also been investigated and provide efficient methods for the construction of highly strained pentacyclic frameworks from norbornadiene.
Journal of the American Chemical Society published new progress about 4141-48-4. 4141-48-4 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Allyldiphenylphosphine oxide, and the molecular formula is C15H15OP, HPLC of Formula: 4141-48-4.
Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia