Synthesis and Diels–Alder cycloaddition reaction of norbornadiene and benzonorbornadiene dimers

Abstract

SummaryDimeric forms of norbornadiene and benzonorbornadiene were synthesized starting with known monobromide derivatives. The Diels–Alder cycloaddition reaction of dimers with TCNE and PTAD was investigated and new norbornenoid polycyclics were obtained. All compounds were characterized properly using NMR spectroscopy.

Using light and a molecular switch to ‘lock’ and ‘unlock’ the Diels–Alder reaction

“…N-Ethylmaleimide was chosen as the least reactive, [4][5][6]10,14,20,21 diethyl dicyanofumarate as having intermediate reactivity 3,11 and tetracyanoethylene as the most reactive dienophile. 22,23 The last variable we included were the specific functional groups decorated onto the two thiophene rings. Phenyl (1a), chloro (1b) and ethoxycarbonyl (1c) groups impart different combinations of steric and electronic contributions to the Diels-Alder reaction equilibria and may also affect the temperature dependency.…”

Unveiling the Unexpected Reactivity of Electrophilic Diazoalkanes in [3+2] Cycloaddition Reactions within Molecular Electron Density Theory

“…The MPWB1K/6-311G (d,p) reactivity indices are gathered in Table S3 in Supplementary Material. The electronic chemical potentials µ of DAAs 7−10, µ = −3.63 (7), −4.27 (8), −4.20 (9), and −4.58 (10) eV, are lower than that of NBD 11, µ = −2.94 eV, suggesting that along a polar process the electron density will flux from NBD 11 to DAAs 7-10 via reverse electron density flux (REDF) reactions [70].…”

“…Recently, NBD has also found applications in molecular photoswitches to absorb solar radiation [5], and by 2018, more than 30 thousand publications and patents had reported their production and applications in various fields [1]. The behavior of NBD derivatives in the Wagner-Meerwein rearrangement [6,7], photochemical di-π methane rearrangement [8], Diels Alder reactions [9], catalytic reactions with alkynes [10] and several other instances [1] have established their uniqueness as organic reagents and fostered their wide synthetic applications in [3+2] cycloaddition (32CA) reactions to form isoxazolidines, triazoles, carbocycles and other heterocycles of biological and environmental relevance [11][12][13][14][15]. In 2001, Tam and coworkers [16,17] reported the highly regio-and stereoselective intramolecular 32CA reactions of NBD-tethered nitrones and nitrile oxides (Scheme 1).…”

Selectfluor and Alcohol Mediated Synthesis of Bicyclic Oxyfluorination Compounds by Wagner-Meerwein Rearrangement

“…On the other hand, with unusual geometry and high reactivity norbornadiene and benzonorbornadiene derivative bicyclic compounds attract great attention by researchers with their use as building blocks in different application areas such as polymers, solar energy storage materials, supramolecular and bioactive compounds. [13][14][15][16][17] To the best of our knowledge, although the oxifluorination of various olefins with water and alcohols is known in the literature, [18][19][20][21][22][23][24][25][26] there is no systematic study on the oxifluorination of bicyclic alkenes.…”