[4 + 2] Cycloadditions of diphenylketene with a highly substituted 1,3-diene

Diels–Alder [4+2] Cycloadditions of C20 with Some Diene and 1,2- Dioxo Compounds: A Theoretical Study

Diels–Alder [2+4] cycloaddition products of the reaction between C20 and C4H4X2 or C2O2X2 (X = H, F, Cl, CH3, NH2, NO2, and OH) were studied atB3LYP level of theory with 6-31G, 6-31G(d, p) and 6-311G(d, p) basis...

diels–alder [4+2] cycloadditions of c20 with some diene and 1,2- dioxo compounds: a theoretical study

diels–alder [2+4] cycloaddition products of the reaction between c20 and c4h4x2 or c2o2x2 (x = h, f, cl, ch3, nh2, no2, and oh) were studied atb3lyp level of theory with 6-31g, 6-31g(d, p) and 6-311g(d, p) basis sets. the homo–lumo gaps of kohn–sham orbitals for most of the adducts show evident increase compared with the gap value of c20, suggestive of more stability in the adducts. the thermod...

Asymmetric synthesis of highly substituted beta-lactones by nucleophile-catalyzed [2+2] cycloadditions of disubstituted ketenes with aldehydes.

Nickel-catalyzed [4+2] cycloaddition for highly substituted arenes.

Nickel(0) catalyzed [4+2] cycloaddition of electron-deficient dienes to alkynes and subsequent aromatization gave highly substituted arenes. This formal inverse electron-demand Diels-Alder cycloaddition is attributed to the formation of a seven-membered nickelacycle from a diene and an alkyne.

[6 + 2] AND [4 + 2] CYCLOADDITION REACTION OF DIPHENYLKETENE AND CYCLOHEPTATRIENE

The cycloaddition reaction of diphenylketene and cycloheptatriene is studied. The reaction proceeds via a highly asynchronous reaction path to the zwitterionic 6 as intermediate. Subsequent CC- bond formation yields 8, 8 diphenylbicyclo [4. 2. I] nona-2, 4-dien-7-one (1) and 7,7-diphenylbicycol [3.2.2] nona-2, 8-dien-ri-one (2) in a 1:1 ratio as formal [6+2] and [4+2] cycloaddition products