Further Synthetic Applications of Functionalized 1,3-Dipoles

1975 ◽  
Vol 53 (24) ◽  
pp. 3782-3790 ◽  
Author(s):  
J. William Lown ◽  
B. Erik Landberg
Keyword(s):  
Ring Closure ◽  
Ethyl Diazoacetate ◽  
Fused Heterocycles ◽  
Leaving Group ◽  
Nitrile Imines ◽  
Azomethine Imines

Reactions of nitrile imines, azomethine imines, and ethyl diazoacetate (as representatives of functionalized 1,3-dipoles) with reactive olefins lead to a series of novel fused heterocycles after suitable ring closure. The influence of the nature of the heterocyclic leaving group and the substituents in the phenacyl residue in a group of phenacylimidazolium salts on the course of their reaction to produce 1,2-dihydrofurans and perhydropyrazolopyrroles is investigated.

DENSITY FUNCTIONAL STUDY OF SELECTED MONO-ZINC AND GEM-DIZINC RADICAL CARBENOID CYCLOPROPANATION REACTIONS: OBSERVATION OF AN EFFICIENT RADICAL ZINC CARBENOID CYCLOPROPANATION REACTION AND THE INFLUENCE OF THE LEAVING GROUP ON RING CLOSURE

2003 ◽  
Vol 02 (03) ◽  
pp. 357-369 ◽  
Author(s):  
CUNYUAN ZHAO ◽  
DONG-QI WANG ◽  
DAVID LEE PHILLIPS
Keyword(s):  
Density Functional ◽  
Theoretical Study ◽  
Radical Reaction ◽  
Ring Closure ◽  
Functional Study ◽  
Reaction Step ◽  
Leaving Group ◽  
Reaction Barriers ◽  
Leaving Groups ◽  
Zinc Carbenoid

We report a theoretical study of the cyclopropanation reactions of EtZnCHI, (EtZn)2CH EtZnCHZnI, and EtZnCIZnI radicals with ethylene. The mono-zinc and gem-dizinc radical carbenoids can undergo cyclopropanation reactions with ethylene via a two-step reaction mechanism similar to that previously reported for the CH2I and IZnCH2 radicals. The barrier for the second reaction step (ring closure) was found to be highly dependent on the leaving group of the cyclopropanation reaction. In some cases, the (di)zinc carbenoid radical undergoes cyclopropanation via a low barrier of about 5–7 kcal/mol on the second reaction step and this is lower than the CH2I radical reaction which has a barrier of about 13.5 kcal/mol for the second reaction step. Our results suggest that in some cases, zinc radical carbenoid species have cyclopropanation reaction barriers that can be competitive with their related molecular Simmons-Smith carbenoid species reactions and produce somewhat different cyclopropanated products and leaving groups.

Critical importance of leaving group ‘softness’ in nucleophilic ring closure reactions of ambident anions to 1,2-diazetidines

2010 ◽  
Vol 51 (2) ◽  
pp. 382-384 ◽  
Author(s):  
Michael J. Brown ◽  
Guy J. Clarkson ◽  
David J. Fox ◽  
Graham G. Inglis ◽  
Michael Shipman
Keyword(s):  
Ring Closure ◽  
Critical Importance ◽  
Leaving Group ◽  
Ambident Anions

scholarly journals Photochemical electrocyclic ring closure and leaving group expulsion from N-(9-oxothioxanthenyl)benzothiophene carboxamides

2013 ◽  
Vol 12 (2) ◽  
pp. 309-322 ◽  
Author(s):  
Majher I. Sarker ◽  
Tasnuva Shahrin ◽  
Mark G. Steinmetz ◽  
Qadir K. Timerghazin
Keyword(s):  
Ring Closure ◽  
Leaving Group

Phosphane-Catalyzed [3+3] Annulation of C,N-Cyclic Azomethine Imines with Ynones: A Practical Method for Tricyclic Dinitrogen-Fused Heterocycles

2016 ◽  
Vol 358 (12) ◽  
pp. 1880-1885 ◽  
Author(s):  
Zhen Li ◽  
Hao Yu ◽  
Yang Liu ◽  
Leijie Zhou ◽  
Zhanhu Sun ◽  
...  
Keyword(s):  
Practical Method ◽  
Fused Heterocycles ◽  
Azomethine Imines

ChemInform Abstract: Regiospecific Ring Closure Reactions of 1,3-Diphenylthiobarbituric Acid and Dimedone: Formation of Spiro vs Fused Heterocycles.

ChemInform ◽  
2014 ◽  
Vol 45 (40) ◽  
pp. no-no
Author(s):  
Anita Pati ◽  
Poulomi Majumdar ◽  
Sarita Garnayak ◽  
Ajaya K. Behera ◽  
Rajani K. Behera
Keyword(s):  
Ring Closure ◽  
Fused Heterocycles

CuI-Catalyzed [3+2] Cycloaddition of Hindered Vinylidenebisphosphonates (VBP) with Azomethine Imines for Highly Regioselective Access to Dinitrogen-Heterobicycle-Containing Bisphosphonates

Synthesis ◽  
2018 ◽  
Vol 50 (13) ◽  
pp. 2601-2607
Author(s):  
Zhongxiang Zhu ◽  
Qinghe Wang ◽  
Dulin Kong ◽  
Tiao Huang ◽  
Mingshu Wu
Keyword(s):  
Biological Activity ◽  
Low Cost ◽  
Cycloaddition Reaction ◽  
Dipolar Cycloaddition ◽  
Atom Economy ◽  
Mild Conditions ◽  
Synthetic Strategy ◽  
Fused Heterocycles ◽  
Azomethine Imines ◽  
High Stereoselectivity

A concise, atom-economic, and highly regioselective synthetic strategy for the construction of several dinitrogen-fused heterocycles bearing bisphosphonates by 1,3-dipolar cycloaddition reaction of azomethine imines with tetraethyl vinylidene-1,1-bisphosphonate in the presence of CuI in toluene media has been developed. The targeted compounds were obtained in good yields and with excellent regioselectivity. This method for the synthesis of gem-bisphosphonates (BPs) is particularly attractive due to features such as low cost, mild conditions, atom economy, high stereoselectivity, and potential biological activity of the product.

Thermal [3+2] cycloaddition reaction of azomethine imines with allenoates for dinitrogen-fused heterocycles

Tetrahedron ◽  
2012 ◽  
Vol 68 (10) ◽  
pp. 2349-2356 ◽  
Author(s):  
Risong Na ◽  
Honglei Liu ◽  
Zhen Li ◽  
Bo Wang ◽  
Jun Liu ◽  
...  
Keyword(s):  
Cycloaddition Reaction ◽  
Fused Heterocycles ◽  
Azomethine Imines
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