Resonance-stabilized ?-naphthylmethyl carbocations and derived spiro compounds 4. T-ansformations of 4-dimethylamino-5-methoxynaphthylmethyl carbocation in the presence of protic and Lewis acids. The formation of an asymmetrical spiro compound

1996 ◽  
Vol 45 (8) ◽  
pp. 1934-1938
Author(s):  
A. F. Pozharskii ◽  
N. V. Vistorobskii ◽  
M. I. Rudnev ◽  
A. I. Chernyshev
Keyword(s):  
Lewis Acids ◽  
Spiro Compounds ◽  
Spiro Compound ◽  
Naphthylmethyl Carbocations

Formation of a spiro compound via coupling of a cyclopentadienyl ligand with a diene moiety of titanacyclopentadiene

2017 ◽  
Vol 46 (47) ◽  
pp. 16408-16411 ◽  
Author(s):  
Masayoshi Bando ◽  
Yuki Mizukami ◽  
Kiyohiko Nakajima ◽  
Zhiyi Song ◽  
Tamotsu Takahashi
Keyword(s):  
Spiro Compounds ◽  
Spiro Compound ◽  
Cyclopentadienyl Ligand

The treatment of titanacyclopentadienes with bismuth(iii) chloride gave spiro compounds in moderate yields.

Hosoya polynomials of general spiro hexagonal chains

Filomat ◽  
2014 ◽  
Vol 28 (1) ◽  
pp. 211-215 ◽  
Author(s):  
Xianyong Li ◽  
Xiaofan Yang ◽  
Guoping Wang ◽  
Rongwei Hu
Keyword(s):  
Organic Chemistry ◽  
Benzene Ring ◽  
Spiro Compounds

Spiro hexagonal chains are a subclass of spiro compounds which are an important subclass of Cycloalkynes in Organic Chemistry. This paper addresses general spiro hexagonal chains in which every hexagon represents a benzene ring, and establishes the formulae for computing the Hosoya polynomials of general spiro hexagonal chains.

scholarly journals Theoretical Insight into the Reversal of Chemoselectivity in Diels-Alder Reactions of α,β-Unsaturated Aldehydes and Ketones Catalyzed by Brønsted and Lewis Acids

Organics ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 38-49
Author(s):  
Lakhdar Benhamed ◽  
Sidi Mohamed Mekelleche ◽  
Wafaa Benchouk
Keyword(s):  
Lewis Acids ◽  
Major Product ◽  
Diels Alder ◽  
Unsaturated Ketone ◽  
Unsaturated Aldehydes ◽  
Aldehydes And Ketones ◽  
Theoretical Insight ◽  
Insight Into ◽  
Good Agreement

Experimentally, a reversal of chemoselectivity has been observed in catalyzed Diels–Alder reactions of α,β-unsaturated aldehydes (e.g., (2E)-but-2-enal) and ketones (e.g., 2-hexen-4-one) with cyclopentadiene. Indeed, using the triflimidic Brønsted acid Tf2NH as catalyst, the reaction gave a Diels–Alder adduct derived from α,β-unsaturated ketone as a major product. On the other hand, the use of tris(pentafluorophenyl)borane B(C6F5)3 bulky Lewis acid as catalyst gave mainly the cycloadduct of α,β-unsaturated aldehyde as a major product. Our aim in the present work is to put in evidence the role of the catalyst in the reversal of the chemoselectivity of the catalyzed Diels–Alder reactions of (2E)-but-2-enal and 2-Hexen-4-one with cyclopentadiene. The calculations were performed at the ωB97XD/6-311G(d,p) level of theory and the solvent effects of dichloromethane were taken into account using the PCM solvation model. The obtained results are in good agreement with experimental outcomes.

Sign in / Sign up

Export Citation Format

Share Document