Simonsen, Klaus B.; Svenstrup, Niels; Roberson, Mark; Jorgensen, Karl Anker published an article on January 31 ,2000. The article was titled 《Development of an unusually highly enantioselective hetero-Diels-Alder reaction of benzaldehyde with activated dienes catalyzed by hyper-coordinating chiral aluminum complexes》, and you may find the article in Chemistry – A European Journal.Reference of (R)-3,3′-Diiodo-2,2′-bis(methoxymethoxy)-1,1′-binaphthalene The information in the text is summarized as follows:
Benzaldehyde and Danishefsky’s diene [(E)-MeOCH:CHC(Me3SiO):CH2] underwent a stereoselective Diels-Alder cycloaddition in Me3COMe in the presence of >2 mol% (R)-binaphthol derivs I [R = H, MeO, Me(CH2)5O, Me(CH2)6] and trimethylaluminum to give the dihydropyran I (R1 = H) in up to 97% yield and 99.4% ee. I [R = Me(CH2)5O] was the most effective catalyst, giving product in high yields and up to 99.4% ee; I [R = MeO, Me(CH2)6] with either similar steric bulk and no oxygens or a methoxy group with coordination capacity but no steric bulk gave II (R1 = R2 = H) in slightly lower yields and enantiomeric excesses (50-95% yields and 82-96% ee), while the unsubstituted I (R = H) gave product in both diminished yield and ee (29% yield, 65% ee). Changes in the aluminum source from trimethylaluminum to either triethylaluminum or to dimethylaluminum chloride significantly decreased the yield and stereoselectivity of the Diels-Alder cycloaddition reactions. Reaction of dimethyl-Danishefsky’s diene [(1E,3Z)-MeOCH:C(Me)C(OSiMe3):CHMe] with benzaldehyde gave the (R,R)-enantiomer of II (R1 = R2 = Me), indicating that the stereoselectivity of the Diels-Alder cycloaddition is based on an endo-transition state. Based on the exptl. results the mechanism for the hetero-Diels-Alder reaction is discussed and it is postulated that hypercoordination to the chiral aluminum Lewis acid center is of importance for the reaction. In the part of experimental materials, we found many familiar compounds, such as (R)-3,3′-Diiodo-2,2′-bis(methoxymethoxy)-1,1′-binaphthalene(cas: 189518-78-3Reference of (R)-3,3′-Diiodo-2,2′-bis(methoxymethoxy)-1,1′-binaphthalene)
(R)-3,3′-Diiodo-2,2′-bis(methoxymethoxy)-1,1′-binaphthalene(cas: 189518-78-3) belongs to organic iodides. Alkyl iodides react at a faster rate than alkyl fluorides due to the weak C-I bond.Reference of (R)-3,3′-Diiodo-2,2′-bis(methoxymethoxy)-1,1′-binaphthaleneIodo alkanes participate in a variety of organic synthesis reactions, which include the SimmonsSmith reaction (cyclopropanation using iodomethane), Williamson ether synthesis, Wittig reaction, Grignard reaction, alkyl coupling reactions, and Wurtz reaction.
Referemce:
Iodide – Wikipedia,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com