MELŠA, Petr, Michal ČAJAN, Zdeněk HAVLAS a Ctibor MAZAL. Substituent Effect on exo Stereoselectivity in the 1,3-Dipolar Cycloaddition Reaction of Tulipalin A with Nitrile Ylides. Journal of Organic Chemistry. 2008, roč. 73, č. 8, s. 3032-3039. ISSN 0022-3263.
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Základní údaje
Originální název Substituent Effect on exo Stereoselectivity in the 1,3-Dipolar Cycloaddition Reaction of Tulipalin A with Nitrile Ylides
Název česky Substituent Effect on exo Stereoselectivity in the 1,3-Dipolar Cycloaddition Reaction of Tulipalin A with Nitrile Ylides
Autoři MELŠA, Petr (203 Česká republika), Michal ČAJAN (203 Česká republika), Zdeněk HAVLAS (203 Česká republika) a Ctibor MAZAL (203 Česká republika, garant).
Vydání Journal of Organic Chemistry, 2008, 0022-3263.
Další údaje
Originální jazyk angličtina
Typ výsledku Článek v odborném periodiku
Obor 10401 Organic chemistry
Stát vydavatele Spojené státy
Utajení není předmětem státního či obchodního tajemství
Impakt faktor Impact factor: 3.952
Kód RIV RIV/00216224:14310/08:00033644
Organizační jednotka Přírodovědecká fakulta
UT WoS 000254883700007
Klíčová slova česky CH-pi interakce; substituční efekt; stereoselektivita; cykloadice
Klíčová slova anglicky CH-pi Interaction; Substituent effect; stereoselectivity; cycloaddition
Štítky cycloaddition, stereoselectivity, Substituent effect
Příznaky Mezinárodní význam, Recenzováno
Změnil Změnil: doc. RNDr. Ctibor Mazal, CSc., učo 22. Změněno: 24. 3. 2010 16:47.
Anotace
1,3-Dipolar cycloaddition reactions of dihydro-3-methylene-2(3H)-furanone (Tulipalin A) with various benzonitrile(p-X-benzylide) ylides prefer formation of exo-cycloadducts in the extent of corresponding to an increasing electron donor character of the substituent X in p-position of benzylide phenyl ring of 1,3-dipolar reagent. The substituent effect on diastereoselectivity of the 1,3-DC reaction is rationalized in terms of CH/p interaction between dipole and dipolarophile in an exo-transition state. The interaction is demonstrated by the correlation of the observed diastereoselectivities with substituent Hammett sigma constants, which shows a small negative r value. A certain contribution of CO/p interaction between lactone carbonyl and the substituted phenyl ring to mediation of the substituent effect is also discussed. The energy profiles of both reaction pathways were analyzed using DFT and RI-MP2 theoretical approaches. Calculated energy and structural differences between located transition states are consistent with reaction diastereoselectivities.
Anotace česky
1,3-Dipolar cycloaddition reactions of dihydro-3-methylene-2(3H)-furanone (Tulipalin A) with various benzonitrile(p-X-benzylide) ylides prefer formation of exo-cycloadducts in the extent of corresponding to an increasing electron donor character of the substituent X in p-position of benzylide phenyl ring of 1,3-dipolar reagent. The substituent effect on diastereoselectivity of the 1,3-DC reaction is rationalized in terms of CH/p interaction between dipole and dipolarophile in an exo-transition state. The interaction is demonstrated by the correlation of the observed diastereoselectivities with substituent Hammett sigma constants, which shows a small negative r value. A certain contribution of CO/p interaction between lactone carbonyl and the substituted phenyl ring to mediation of the substituent effect is also discussed. The energy profiles of both reaction pathways were analyzed using DFT and RI-MP2 theoretical approaches. Calculated energy and structural differences between located transition states are consistent with reaction diastereoselectivities.
Návaznosti
MSM6198959218, záměrNázev: Komplexní sloučeniny a oxidy přechodných kovů s využitím v bioaplikacích a nanotechnologiích
VytisknoutZobrazeno: 16. 4. 2021 17:26