774128-72-2

Upstream product

• 105-09-9 1,4-bis(mercaptomethyl)benzene 
• 51657-08-0 4,7-bis(bromomethyl)<2.2>paracyclophane 
• 85555-53-9 C₂₆H₂₆Se₂ 
• 82456-99-3 1,2,4,5-Tetrakis(mercaptomethyl)benzene 
• 117912-00-2 2-(2,4,5-Tris-carbamimidoylsulfanylmethyl-benzyl)-isothiourea; hydrobromide 
• 15442-91-8 1,2,4,5-tetrabromomethylbenzene 
• 121511-54-4 triple-layered tetrathia<3.3><3.3>paracyclophane 

Relevant academic research and scientific papers

DESELENATION OF DISELENACYCLOPHANES - A NEW SYNTHETIC METHOD OF CYCLOPHANES-

Several diselenacyclophanes were prepared by coupling of bisselenocyanates and bis(bromomethyl)benzenes in good yields.The benzyne Stevens rearrangement-Raney Ni hydrogenolysis method gave good yields of double- and triple-layered cyclophanes from the diselenides, though the flash pyrolysis method gave them in low yields.

Synthesis, Structure, and Properties of Triple-Layered Naphthalenophane

The title compound was synthesized in a similar manner to a simple access to triple-layered paracyclophane.Its structure was elucidated by X-ray crystallographic analysis.The outer naphthalene rings are bent into a boat form and the inner naphthalene ring is bent into a twist form.These naphthalenes are stacked in layers within van der Waals contact.Therefore, there is a strong transannular ?-electronic interaction between them, which brings about characteristic bathochromism, hyperchromism, and broadening in the electronic spectrum.These effects are more prominent than those of the double-layered homologue.

New Synthetic Method of Cyclophanes via Diselenacyclophanes

Syntheses of cyclic diselenides through diselenolates and the following deselenation reactions by means of three ways were studied.The preparation of the cyclic diselenides in the presence of excess sodium borohydride gave thirty-eight diselenides containing diselenacyclophanes and alicyclic diseleno compounds in high yields in addition to two triple-bridged selenacyclophanes.Photodeselenation of the diselenides in tris(dimethylamino)phosphine afforded series of cyclophanes in much higher yields than those of the other two methods, i.e. benzyne-Stevens rearrangement/Raney nickel hydrogenolysis and pyrolytic deselenation at ca. 650 deg C.The present study demonstrates that the photodeselenation method combined with the synthesis of their precursor diselenides, is much superior to the conventional dechalcogenation methods.

SYNTHESIS OF CYCLOPHANES BY PHOTODESELENATIVE RINGCONTRACTION

Several cyclophanes were prepared by photodeselenation of diselenacyclophanes with hexamethylphosphorous triamide in excellent yields, compared with the other chalcogen-atom extrusion methods.