Catalytic Ring Opening of Cycloalkanes on Ir Clusters: Alkyl Substitution Effects on the Structure and Stability of C–C Bond Cleavage Transition States

2015 ◽  
Vol 119 (5) ◽  
pp. 2597-2613 ◽  
Author(s):  
David W. Flaherty ◽  
Alper Uzun ◽  
Enrique Iglesia
Keyword(s):  
Ring Opening ◽  
Bond Cleavage ◽  
Transition States ◽  
Substitution Effects ◽  
Structure And Stability ◽  
Alkyl Substitution

Copper-Catalyzed Intramolecular α-C–H Amination via Ring-Opening Cyclization Strategy to Quinazolin-4-ones: Development and Application in Rutaecarpine Synthesis

Synthesis ◽  
2019 ◽  
Vol 51 (16) ◽  
pp. 3160-3170
Author(s):  
Srilaxmi M. Patel ◽  
Harika Chada ◽  
Sonali Biswal ◽  
Sonika Sharma ◽  
Duddu S. Sharada
Keyword(s):  
Ring Opening ◽  
Functional Group ◽  
Bond Cleavage ◽  
Isatoic Anhydride ◽  
General Method

A copper-catalyzed intramolecular α-C–H amination has been developed for the synthesis of quinazolin-4(3H)-one derivatives from commercially available isatoic anhydride and primary and secondary benzylamines via ring-opening cyclization (ROC). This method shows good functional group tolerance and allows access to a range of 2-aryl, 2-alkyl, and spiroquinazolinone derivatives. However, 2-methylquinazolin-4(3H)-one was synthesized from 2-amino-N-isopropylbenzamide by C–C bond cleavage, and N-benzyl-2-(methylamino)benzamide afforded 1-methyl-2-phenylquinazolin-4(1H)-one along with 2-phenylquinazolin-4(3H)-one by N–C bond cleavage for aromatization. It is the first general method to construct the potentially useful 2-methylquinazolin-4(3H)-one by copper-catalyzed intramolecular C–H amination. Also this ROC strategy has been successfully applied to the synthesis of quinazolinone alkaloid rutaecarpine.

Mechanistic insights into a non-heme 2-oxoglutarate-dependent ethylene-forming enzyme: selectivity of ethylene-formation versusl-Arg hydroxylation

2019 ◽  
Vol 21 (19) ◽  
pp. 9957-9968 ◽  
Author(s):  
Junqin Xue ◽  
Jiarui Lu ◽  
Wenzhen Lai
Keyword(s):  
Bond Cleavage ◽  
Transition States ◽  
Ethylene Formation ◽  
Enzyme Selectivity

QM/MM calculations for a non-heme 2-oxoglutarate-dependent ethylene-forming enzyme reveal that the selectivity of ethylene formation versus succinate formation is determined by the relative energies of transition states for the competing CO2 insertion and O–O bond cleavage of the FeII-peroxysuccinate species.

Carbon–nitrogen bond cleavage of pyridine with two molecular substituted allenoates: access to 2-arylpyrimidin-4(3H)-one

2018 ◽  
Vol 54 (100) ◽  
pp. 14128-14131 ◽  
Author(s):  
Tao Jin ◽  
Hongdong Yuan ◽  
Shikuan Su ◽  
Xueshun Jia ◽  
Chunju Li ◽  
...  
Keyword(s):  
Benzene Ring ◽  
Ring Opening ◽  
Pyridine Ring ◽  
Bond Cleavage ◽  
Ring System ◽  
Nitrogen Bond

A DABCO-catalyzed annulation reaction of pyridin-2-amine and substituted allenoates enables the ring-opening of a pyridine ring system and the formation of two new rings including a pyrimidinone ring and a benzene ring.

scholarly journals The Effect of Tb and Sm Ions on the Photochromic Behavior of Two Spiropyrans of Benzoxazine Series in Solution

2008 ◽  
Vol 2008 ◽  
pp. 1-4 ◽  
Author(s):  
Esam Bakeir ◽  
G. M. Attia ◽  
Maria Lukyanova ◽  
Boris Lukyanov ◽  
M. S. A. Abdel-Mottaleb
Keyword(s):  
Relaxation Time ◽  
Ring Opening ◽  
Bond Cleavage ◽  
Lanthanide Ions ◽  
Photochromic Behavior ◽  
First Order ◽  
Color Development ◽  
First Order Kinetics ◽  
Thermal Bleaching ◽  
Color Enhancement

The photochromism of [7′-hydroxy-8′-formyl-3-methyl-4-oxospiro[1,3-benzoxazin-2,2′-[2H-1]benzopyran],SP(I),[7′-hydroxy-8′-formyl-3-benzyl-4-oxospiro[1,3-benzoxazin-2,2′-[2H-1]benzopyran] SP(II) and their coordination with Tb3+and Sm3+ ions have been studied in DMF. UV/vis induced-color development due to heterolytic bond cleavage of SP(I) and SP(II) is greatly influenced by complexation with the lanthanide ions. The irradiation-induced color enhancement due to ring opening and thermal decoloration of the open forms of SP(I), SP(II) follows first-order kinetics. Physical characteristics of the studied systems such as colorability and relaxation time of thermal bleaching parameters were determined. Moreover, light-energy transfer-induced luminescence of lanthanide ions via coordination with the two spirobenzoxazines was monitored.

Recent Advances in the Chemistry of 2-Acylaziridines

Synthesis ◽  
2017 ◽  
Vol 49 (23) ◽  
pp. 5093-5104 ◽  
Author(s):  
Alena Pankova ◽  
Mikhail Kuznetsov
Keyword(s):  
Carbonyl Group ◽  
Ring Opening ◽  
Bond Cleavage ◽  
Aziridine Ring ◽  
Reaction Selectivity ◽  
Recent Advances ◽  
Nitrogen Containing Compounds

This review highlights recent achievements in the transformations of 2-acylaziridines toward the synthesis of cyclic and acyclic nitrogen-containing compounds. The influence of a carbonyl group on reaction selectivity is discussed.1 Introduction2 Reactions via C–C Bond Cleavage3 Reactions via C–N Bond Cleavage3.1 Reactions Starting with the Aziridine Ring Opening3.2 Reactions Starting at the Carbonyl Group4 Conclusion

Sign in / Sign up

Export Citation Format

Share Document