An efficient protocol for the synthesis of a range of 1,2-benzisoxazoles using an improved 1,3-dipolar cycloaddition of nitrile oxides and benzyne is described. Key to the procedure is the in situ generation of the reactive nitrile oxide and benzyne reactants simultaneously.

In this communication, we report our femtosecond real-time observation of the dynamics for the three didehydrobenzene molecules (p-, m-, and o-benzyne) generated from 1,4-, 1,3-, and 1, 2-dibromobenzene, respectively, in a molecular beam, by using femtosecond time-resolved mass spectrometry. The time required for the first and the second C-Br bond breakage is less than 100 fs; the benzyne molec...

Abstract A capture reaction of hexadehydro-Diels–Alder (HDDA) derived benzyne with various substituted oxazoles is reported. With methyl, hydrogen, or phenyl as the substituent at 2-position oxazole, tetraynes afforded epoxyanthracene derivatives underwent dicarbonylation on benzene ring. The does not require any catalyst additive. mechanism behind was investigated. obtained polycyclic product ...

reactions of 1 ,zdihydropyridines (la-c) and 1,4-dihydropyridines (2a-c) in the presence of benzyne (3) under thermal conditions, and in the case of (2c) under photochemical conditions, have been investigated. benzyne acts as an oxidizing agent to convert dihydropyridine (la) and (2a) to the corresponding pyridine (4) or adds as a dienophile to (lb-c).

An efficient synthesis of a range of 1,2-benzisoxazoles using an improved 1,3-dipolar cycloaddition of nitrile oxides and benzyne is described. Key to the procedure is the in situ generation of the reactive nitrile oxide and benzyne reaction partners mediated by TBAF. Reactions are complete within 30 s, giving the target products in good to excellent yield.

Reactions of 1 ,Zdihydropyridines (la-c) and 1,4-dihydropyridines (2a-c) in the presence of benzyne (3) under thermal conditions, and in the case of (2c) under photochemical conditions, have been investigated. Benzyne acts as an oxidizing agent to convert dihydropyridine (la) and (2a) to the corresponding pyridine (4) or adds as a dienophile to (lb-c).

The competence between the possible reaction pathways in the reaction of different cycloalkanes and o-benzyne has been computationally explored. Systems able to undergo complete desaturation by consecutive double hydrogen atom transfer reactions are suggested.

We have devised a novel 1,3-benzdiyne equivalent, capable of quadruple functionalization by sequential benzyne generation and reaction with arynophiles. The key features of this method include the chemoselective generation of two triple bonds in a single benzene ring under fluoride-mediated mild conditions, and the regiocontrol of each benzyne reaction by the substituent next to the triple bond...

Modification of individual chemisorbed benzene molecules on Cu~100! has recently been performed in atomic manipulation experiments @J. Phys. Chem. A. 104, 2463 ~2000!; Surf. Sci 451, 219 ~2000!#. Benzene dissociates under controlled voltage pulses in a scanning tunneling microscope ~STM! junction. The reaction is characterized as a dehydrogenation process and the fragments are identified as ben...