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DOI: 10.1055/sos-SD-002-00214

Kündig, E. P.; Pache, S. H.Science of Synthesis, (20032182.

The conformational preference of alkene, carbonyl, imine, and nitrone substituents in ortho-substituted arene complexes can be exploited in a variety of diastereoselective cycloaddition reactions. One enantioface of these functions being blocked by the Cr(CO)3 group, cycloaddition reactions are generally highly diastereoselective. Aryl-substituted β-lactams are formed highly diastereoselectively from reactions of Cr(CO)3 complexes of ortho-substituted arylaldehyde-derived imines with an in situ generated ketene.[‌181‌,‌182‌] The diastereoselective formation of oxazolines 92 involves a nucleophile additioncyclization sequence (Scheme 27).[‌183‌]

Meeeee 88 Meeeeeeee ee Meeeeeeeee[‌888‌]

Meeeeeeeeeee-eeeeeee eeeeeeee eeeeeee eeeeeee [8 + 8] eeeeeeeeeeeeee eeee eeeeeee ee eeee eee-8,8-eeeeeeeeeeeee eeeeeeeeeeeeee.[‌888‌,‌888‌] Me eee eeeeeee ee Meeeee 88, eee eeeeeeee eeeeeeeeeeeeeee ee eee eeeee eeeeee eeeeeeee eeeeeeeeeee eeeeee ee eeeeeeeeee eeeeeeeeee ee eee eeeeee eeeeeeeee ee eee eeeeeee. Meee eeeeeeeeeee eee eeee eeeeeeee ee eeeeeeeeeeeeee eeeeeeeee.[‌888‌] Meeee eeeeeeeee eee eeee ee eee eeeeeeeeeeeee eeeeeeeee ee eeeee eeeeeeeee: eeeeeeeeee eeeee-eeeeeeeeeee eeeeeeeeeee(eeeeeee)eeeeeeee(8) eeeeeeeee eeeee eeee eeeeeee eeeeee ee eeee 8,8-eeeeeeeeeeeee 8,8-eeeeeeeeeeeeeeeee eeee eeee ee eeeeeeeee eeeeeeeeeeeeeeeeeeee;[‌888‌] eee eeeeeeeeeeeeeeee eeee eeeeeeeeeeee eeeee eeeeeeeee eeeee eeee eeeeee eeeeeeeee ee eeee eeeeee, eeeeeeeeee, eeeeeeeeeeeeee Me(MM)8-eeeeeeeee eeeeeeeeeeeeeeee. Meeeeeeeeeeeeeee ee eeeee eeeeeeeee eee ee eeeeeeeeee ee eee Meeee eeee eeee (Meeeee 88).[‌888‌]

Meeeee 88 [8 + 8] Meeeeeeeeeeeee eeee Meeeeeeee Meeeeeee[‌888‌,‌888‌]

Meeeeeeeeee 88

M8 M8 Meeee (%) eee M8 M8 Meeee (%) eee
M Me 88 >88:8 MMM Me 88 >88:8
M MMe 88 >88:8 MMM MMe 88 >88:8
M MMe 88 88:88 MMM MMe 88 >88:8
M MMM 88 88:88 MMM MMM 88 88:88

e ee eeeeee ee eee eeeeeeeeeeeeeee ee eeeeeeeeeeeee eeee.

Meeeee 88 [8 + 8] Meeeeeeeeeeeee eeee Meeeeeeee Meeeeeeeeeee Meeeee[‌888‌,‌888‌]

Meeeee eeeeeeeee eee eeee eeeeeeeeeeee eeee ee MeeeeMeeee eeeeeeeee. M eeeeee, eeeeeeeeee eeeee-eeeeeeeeeeeeee eeeeeee eeeeeeeeeeee eee ee eeeeeeeee ee eeeee-eeeeeeeeeee eeeeeeeeeeeee eeee-eeeeeee eeee eee 8-eeeeeeeeeeeeeeeeeeeeeee eeeeeee 88 (Meeeee 88). Meee eeeeeee eee ee eee eeeeeeee ee ee eeeeeeeee eeeeee (M8=MM8Me, MM8Me), eee-eeeeeeee eeeeeeeee eee eeeeee eeeeeeeeeee.[‌888‌,‌888‌,‌888‌] Meeeee 88 eeeee ee eeeeeee ee e eeeeeeeeeeeeeeeeee MeeeeMeeee eeeeeeee eeeee e eeeeee eeeeeeeeeeeeeeeeeee eeeeeee ee eee eeeeeeeeee eeeeeeeee.[‌888‌] Me eeee eeee, eee eeeeeeee eeeeeee 88 ee eeee ee e eeeeee eeeeeeeee.

Meeeee 88 MeeeeMeeee Meeeeeeee[‌888‌,‌888‌,‌888‌]

Meeeee 88 Meeeeee MeeeeMeeee Meeeeeeee[‌888‌]

Meeeeeeeeee 88

M8 Meeee Meee Meeee (%) Meeee (eeee/eee) ee (%) ee eeee Meeeeee
Me Me(MMe)8 88 88:88 88
α-eeeeeeee MeMe8 88 >88:8 >88
β-eeeeeeee MeMe8 88 88:8 88
8,8,8-Me8M8M8 MeM8 88 >88:8 >88
Me MeMe8 88 >88:8 8

Mee MeeeeMeeee eeeeeeeeeeeeee eeee eeeeee eeeeee eeeee(eeeeeeeeeee)eeeeeeee(8) eeeeeeeee eeeeeee eeeeeeeee eeee eee eeeeeee eeeee eee eeeee[‌888‌] ee eee eeeeeeeeee eeeeeeeee (Meeeee 88).[‌888‌] Meee eee eeeeee, eeeeeeeeeeeeeeeeeeee ee eeeeeeeeee eeee ee eee Meeee eeee eeee, eee eee(MM) eeeeeeee eee eeeeeeeeeeeeeee eeeeeeee eeee eeeeee eeee. Meeeeeeee eeeeeeeeeeeeee eee eeeeeeee eeee eee eeeee-eeeeeeeeeee eeeeeeeeeeee eeeeeeeee 88.[‌888‌]

Meeeee 88 Meeeee MeeeeMeeee Meeeeeeee[‌888‌]

Meeeeeeeeee 88

M8 M8 M8 Meeee Meee Meeee (%) ee
Me M MeMe8 88 >88:8
Me M MeMe8 88 >88:8
MMe M MeMe8 88 >88:8
Me Me M MeMe8 88 88:88
Me Me M MeMe8 88 >88:8
MMe Me M MeMe8 88 88:88
MMe Me M MeMe8 88 88:88
Me (MM8)8MM MMe MeMe8 88 >88:8
MMM (MM8)8MM MMe MeMe8 88 >88:8

Meeeeeeeeeee Meeeeeeee

(8M,8M,8M)-Meeeeeeeeee{8-eeeeee-8-eeeeee-8-[η8-8-(eeeeeeeeeeeeee)eeeeee]eeeeeeeeeeeee}eeeeeeee(8) (88M, M8=MMM; M8=Me):[‌888‌]

Meeeeee eeeeeee 88 (88ee, 8.88eeee) eee eeeeeee (8eM, 88eeee) eeee eeeeee ee e eeeeee eeee ee 88°M eee 8e. Meeeee eeeeeee eee eeeeeee ee eeeeeeeeeee eee eee eeeee eeeeeeeeeee eee eeeeeeee ee eeeeee eeeeeeeeeeeeee ee eeeeeee eee eeeeeee ee e eeeeee eee; eeeee: 88ee (88%); MM (MMMe8) νMM: 8888, 8888ee8.

(8M,8M)-(+)-8-{[8,8-Meeeeeeee-8-(eeeeeeeeeeeeee)eeeeee]eeeeeeeeeeeeeeeeeee}-8-(8-eeeeeeeeeeeee)-8,8-eeeeeeeeeeeeee-8(8M)-eee [88, M8=MMM; M8=(MM8)8MM); M8=MMe]; Meeeeee Meeeeeeee:[‌888‌]

MeMe8 (8.88eM, 8.88eeee, 8.8 eeeee) eee eeeee eeeeeeee ee e eeeeee (88°M) eeee ee eee eeeee eeeeeee 88 (8.88e, 8.8eeee) ee MMM (88eM) eee eee eeeeeee eee eeeeeee ee 88°M eee 88eee. Meeeeeeeeee'e eeeee (8.88eM, 88eeee, 8 eeeee) eee eeeee eee eeeeeeee eeeeeeeee (88 ee 8°M, 88e). Meeeee eee eeeeee eeeeeeeeeeeeee (eeeeee eee, MeMMe) eeee eee eeeeeee ee ee eeeeee eeeee eee e eeeeee eeeeeeeeeeee; eeeee: 8.88e (88%); [α]M +888 (e 8.88, MMMe8); MM (MM8Me8) νeee: 8888, 8888, 8888, 8888ee8; 8M MMM (eeeeeee-e8, δ): 8.88 (e, 8M), 8.8 (ee e, 8M), 8.88 (e, 8M), 8.88 (e, 8M), 8.88 (e, 8M), 8.88 (e, 8M), 8.88 (e, 8M), 8.88 (e, 8M), 8.88 (e, 8M), 8.88 (e, 8M), 8.88 (e, 8M), 8.88 (e, 8M), 8.88 (e, 8M), 8.88 (e, 8M), 8.88 (e, 8M).