MELŠA, Petr, Michal ČAJAN, Zdeněk HAVLAS and 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, vol. 73, No 8, p. 3032-3039. ISSN 0022-3263.
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Basic information
Original name Substituent Effect on exo Stereoselectivity in the 1,3-Dipolar Cycloaddition Reaction of Tulipalin A with Nitrile Ylides
Name in Czech Substituent Effect on exo Stereoselectivity in the 1,3-Dipolar Cycloaddition Reaction of Tulipalin A with Nitrile Ylides
Authors MELŠA, Petr (203 Czech Republic), Michal ČAJAN (203 Czech Republic), Zdeněk HAVLAS (203 Czech Republic) and Ctibor MAZAL (203 Czech Republic, guarantor).
Edition Journal of Organic Chemistry, 2008, 0022-3263.
Other information
Original language English
Type of outcome Article in a journal
Field of Study 10401 Organic chemistry
Country of publisher United States of America
Confidentiality degree is not subject to a state or trade secret
Impact factor Impact factor: 3.952
RIV identification code RIV/00216224:14310/08:00033644
Organization unit Faculty of Science
UT WoS 000254883700007
Keywords (in Czech) CH-pi interakce; substituční efekt; stereoselektivita; cykloadice
Keywords in English CH-pi Interaction; Substituent effect; stereoselectivity; cycloaddition
Tags cycloaddition, stereoselectivity, Substituent effect
Tags International impact, Reviewed
Changed by Changed by: doc. RNDr. Ctibor Mazal, CSc., učo 22. Changed: 24/3/2010 16:47.
Abstract
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.
Abstract (in Czech)
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.
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MSM6198959218, plan (intention)Name: Komplexní sloučeniny a oxidy přechodných kovů s využitím v bioaplikacích a nanotechnologiích
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