rings5 - FIVE-MEMBERED RING FORMATION 138 5 Membered Rings...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: FIVE-MEMBERED RING FORMATION 138 5 Membered Rings PGF 2 PGE 2 HO HO CO 2 H OH CO 2 H OH HO O Me Me Me Me H Me Me Me Me Hirsutene Isocumene Modhephane 1. Intramolecular S N 2 Reactions 2. Intramolecular Aldol Condensation and Michael Addition 3. Intramolecular Wittig Olefination 4. Ring Expansion and Contraction Reactions a. 3 5 b. 4 5 c. 6 5 5. 1,3-Dipolar additions 6. Nazarov Cyclization 7. Arene-Olefin Photocyclization 8. Radical Cyclizations 9. Others Synthesis 1973 , 397; ACIEE 1982 , 21 , 480; Intramolecular S N 2 Reaction 5-exo-tet: favored O Br LDA O JCSCC 1973 , 233 O Br CO 2 Me O CO 2 Me O CN O CN OH JACS 1974 , 96 , 5268 FIVE-MEMBERED RING FORMATION 139 RO 2 C CO 2 R O O Cl Cl RO 2 C CO 2 R JACS 1979 , 101 , 5081 O TsO O NaH, DMSO JCSCC 1979 , 817 Intramolecular Aldol Condensation 5-exo-trig: favored intramolecular aldol condensation of 1,4-diketones O O R' R O R' R O O CH 3 CH 3 O CH 3 CH 3 TL 1982 , 29, 2237 O Br CO 2 Me O Br CO 2 Me O NaOMe, MeOH JACS 1980 , 102 , 4262 O O O NaOH O O JOC 1983 , 48 , 1217 Intramolecular Michael Addition 5-exo-tet: favored Organic Reactions 1995 , 47 , 315-552 O MeO 2 C O O O JACS 1979 , 101 FIVE-MEMBERED RING FORMATION 139 RO 2 C CO 2 R O O Cl Cl RO 2 C CO 2 R JACS 1979 , 101 , 5081 O TsO O NaH, DMSO JCSCC 1979 , 817 Intramolecular Aldol Condensation 5-exo-trig: favored intramolecular aldol condensation of 1,4-diketones O O R' R O R' R O O CH 3 CH 3 O CH 3 CH 3 TL 1982 , 29, 2237 O Br CO 2 Me O Br CO 2 Me O NaOMe, MeOH JACS 1980 , 102 , 4262 O O O NaOH O O JOC 1983 , 48 , 1217 Intramolecular Michael Addition 5-exo-tet: favored Organic Reactions 1995 , 47 , 315-552 O MeO 2 C O O O JACS 1979 , 101 , 7107 FIVE-MEMBERED RING FORMATION 140 Intramolecular Wittig Olefination Tetrahedron 1980 , 36 , 1717 O C 5 H 11 THPO OTHP O 1) (MeO) 2 P(O)CH 2- 2) Collins C 5 H 11 THPO OTHP O O P(OMe) 2 O base C 5 H 11 THPO OTHP O C 5 H 11 HO OH CO 2 H JOC 1981 , 46 , 1954 Ring Expansion Reactions- 3 5: Vinyl Cyclopropane Rearrangement Organic Reactions 1985 , 33, 247. O O O H O O H O SPh 2 _ O O H OTMS O O H TMSO JACS 1979 , 101 , 1328- 4 5: Reaction of cyclobutanones with Diazomethane O Cl Me CH 2 N 2 O Me Cl Me Me O Cl Cl CH 2 N 2 Me O Cl Cl Me TL 1980 , 21 , 3059 O Cl Cl O CH 3 CH 3 Ph O CH 3 CH 3 Ph O Cl Cl CH 2 N 2 JACS 1987 , 109 , 4752 FIVE-MEMBERED RING FORMATION...
View Full Document

Page1 / 12

rings5 - FIVE-MEMBERED RING FORMATION 138 5 Membered Rings...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online