113334-35-3Relevant academic research and scientific papers
ON THE MULTIPLICITY OF CARBENES CONJUGATED WITH PYRROLE AND FURAN MOIETIES: MOLECULAR ORBITAL CALCULATION AND REACTION OF 2-(1-METHYL)PYRROLYLMETHYLENE AND 2-FURYLMETHYLENE WITH CIS- AND TRANS-STILBENES
Saito, Katsuhiro,Ushida, Takahiro,Fushihara, Hiroshi,Yamashita, Yoshiro,Tanaka, Shoji,Takahashi, Kensuke
, p. 115 - 122 (2007/10/02)
The reaction of 2-(1-methyl)pyrrolylmethylene and 2-furylmethylene with cis- and trans-stilbenes proceeded in a stereospecific manner to give the corresponding cyclopropane derivatives to show that the multiplicities of these carbenes are singlet.The molecular orbital calculation showed that these carbenes are triplet in their ground state and nucleophilic both in singlet and triplet states.
A Dipolar Cycloaddition Approach to Pyrroloindoles Using N--Substituted Indoles
Padwa, Albert,Fryxell, Glen E.,Gasdaska, John R.,Venkatramanan, M. K.,Wong, George S. K.
, p. 644 - 653 (2007/10/02)
The 1,3-dipolar cyloaddition of a number of N--substituted indoles with several dipolarophiles has been investigated.The reaction requires the use of an equivalent amount of silver fluoride and provides a direct and efficient synthesis of the pyrroloindole ring system.The structures of the cycloadducts were established by high-field NMR spectroscopy as well as by several X-ray crystal structures.The cycloaddition reactions show all the characteristics of a concerted reaction, including complete stereospecificity and regioselectivity.The results are consistent with a mechanism that involves the intermediacy of an azomethine ylide.Formation of the dipole is rationalized by assuming that silver ion behaves as a very specific Lewis acid that attacks the indole ring to give a silver bonded carbonium ion.This is followed by a rapid desilylation reaction to give the azomethine ylide.After the cycloaddition step, the resulting silver-bonded intermediate undergoes consecutive loss of silver and a hydrogen to give the observed product.Attempts to extend the cycloaddition methodology to N--substituted enamines and pyrroles are also described.
THERMOLYSIS OF SODIUM SALTS OF TOSYLHYDRAZONES OF SOME HETEROCYCLIC ALDEHYDES IN THE PRESENCE OF SILVER CHROMATE: 1,3 NC MIGRATION OF TOSYL GROUP
Saito, Katsuhiro,Ishihara, Hiraku
, p. 1891 - 1898 (2007/10/02)
The thermal decompositions of sodium salts of tosylhydrazones of furfural, thiophene-2-aldehyde, 1-methylpyrrole-2-aldehyde, and pyridine-2-aldehyde in the presence of silver chromate gave 2-furyl(p-toluenesulfonyl)methane, thiophene-2-(p-toluenesulfonyl)methane, 1-methylpyrrole-2-(p-toluenesulfonyl)methane, and pyridine-2-(p-toluenesulfonyl)methane, respectively, via 1,3 NC migration of tosyl group.The same type of reactions with sodium salts of tosylhydrazones of thiophene-3-aldehyde, pyridine-3-aldehyde, and pyridine-4-aldehyde also afforded the corresponding p-toluenesulfonylmethanes but the yields were slightly lower comparing to the above cases.
