Pericyclic versus pseudopericyclic 1,5-electrocyclization of iminodiazomethanes. An ab initio and density functional theory study / Fabian WMF,Bakulev VA,Kappe CO // JOURNAL OF ORGANIC CHEMISTRY. - 1998. - V. 63, l. 17. - P. 5801-5805.

ISSN/EISSN:

0022-3263 / нет данных

Type:

Article

Abstract:

Density functional (B3LYP/6-311+G{*}{*}) and ab initio (MP2/6-311+G{*}{*} and MP4(SDTQ)/6-311+G{*}{*}// MP2/6-311+G{*}{*}) calculations on the ring closure reactions of (E)- and Z-iminodiazomethane ((E)-5, (Z)-5), vinyldiazomethane 7, and formyldiazomethane 9 to 1H-1,2,3-triazole 6, 3H-pyrazole 8; and 1,2,3-oxadiazole 10, respectively, are reported. (E)-5 cyclizes via a low barrier (ca. 10 kcal mol(-1)) pseudopericyclic nonrotatory transition state. Ring closure of (Z)-5 and 7 proceeds by a monorotatory movement of the imino or vinyl group with a substantially higher barrier (ca. 25 kcal mol(-1)). Despite being endothermic, for the reaction 9 - 10 also a rather low activation energy (ca. 10 kcal mol(-1)) is computed. The NBO analysis is used to interpret the electronic structures of the respective transition states in terms of their pericyclic monorotatory (TS ((Z)-5 --> 6), (TS (7 --> 8)) or pseudopericyclic nonrotatory ((TS ((E)-5 --> 6), (TS (9 --> 10)) nature.

Author keywords:

REACTION TRANSITION STRUCTURES; THEORETICAL PREDICTIONS; VIBRATIONAL FREQUENCIES; ELECTROCYCLIC REACTIONS; ISOMERIZATION; FORMYLKETENE; CONFORMATIONS; IMIDOYLKETENE; NITROSOKETENE; DIAZOIMINE

DOI:

10.1021/jo980238u

Web of Science ID:

ISI:000075750300021

Соавторы в МНС:

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Другие поля

Поле	Значение
Month	AUG 21
Publisher	AMER CHEMICAL SOC
Address	1155 16TH ST, NW, WASHINGTON, DC 20036 USA
Language	English
Keywords-Plus	REACTION TRANSITION STRUCTURES; THEORETICAL PREDICTIONS; VIBRATIONAL FREQUENCIES; ELECTROCYCLIC REACTIONS; ISOMERIZATION; FORMYLKETENE; CONFORMATIONS; IMIDOYLKETENE; NITROSOKETENE; DIAZOIMINE
Research-Areas	Chemistry
Web-of-Science-Categories	Chemistry, Organic
Author-Email	kappeco@balu.kfunigraz.ac.at
ResearcherID-Numbers	Kappe, C. Oliver/C-9771-2011
ORCID-Numbers	Kappe, C. Oliver/0000-0003-2983-6007
Number-of-Cited-References	54
Usage-Count-Last-180-days	1
Usage-Count-Since-2013	10
Journal-ISO	J. Org. Chem.
Doc-Delivery-Number	116XL