Diels- Alder reactions using 4,7-dioxygenated indanones as dienophiles for regioselective construction of oxygenated 2,3-dihydrobenz[f]indenone skeleton

• Natsuno Etomi,
• Takuya Kumamoto,
• Waka Nakanishi and
• Tsutomu Ishikawa

Beilstein J. Org. Chem. 2008, 4, No. 15, doi:10.3762/bjoc.4.15

• -Trioxygenated 2,3-dihydrobenz[f]indenone derivative 21 was exclusively formed on DAR of indanetrione 8 and diene 7 because of selective activation of the C6 carbon due to the presence of additional cross conjugation between the C1 and the C4 carbonyl groups (TS-A, Figure 4). Semiempirical calculation [44] of

Synthesis of 2,6-trans- disubstituted 5,6-dihydropyrans from (Z)-1,5-syn-endiols

• Eric M. Flamme and
• William R. Roush

Beilstein J. Org. Chem. 2005, 1, No. 7, doi:10.1186/1860-5397-1-7

• hydroxyl groups. Selective activation of the allylic alcohol in 2 as a leaving group followed by nucleophilic attack by the homoallylic alcohol will lead to dihydropyran 3. However, activation of the homoallylic alcohol followed by nucleophilic attack by the allylic alcohol will provide the enantiomeric