- Platinum-catalyzed domino reaction with benziodoxole reagents for accessing benzene-alkynylated Indoles
-
Indoles are omnipresent in natural products, bioactive molecules, and organic materials. Consequently, their synthesis or functionalization are important fields of research in organic chemistry. Most works focus on installation or modification of the pyrrole ring. To access benzene-ring-functionalized indoles with an unsubstituted pyrrole ring remains more challenging. Reported herein is a platinum-catalyzed cyclization/alkynylation domino process to selectively obtain C5- or C6-functionalized indoles starting from easily available pyrroles. The work combines, for the first time, a platinum catalyst with ethynylbenziodoxole hypervalent iodine reagents in a domino process for the synthesis of polyfunctionalized arene rings and gives access to important building blocks for the synthesis of bioactive compounds and organic materials.
- Li, Yifan,Waser, Jerome
-
supporting information
p. 5438 - 5442
(2015/04/27)
-
- Novel inhibitors of bacterial biofilms and related methods
-
Multi-cyclic compounds of chemical structure represented by formula given below and compositions thereof are useful for reducing or inhibiting the growth of bacterial biofilms and for controlling bacterial biofilm infections. Such compounds and compositions are also useful in methods for reducing or inhibiting the growth of biofilms and for controlling bacterial biofilm infections involving biofilms.
- -
-
Paragraph 0264; 0265
(2014/05/06)
-
- Inhibitors of bacterial biofilms and related methods
-
Certain multi-cyclic compounds and compositions thereof are useful for reducing or inhibiting the growth of bacterial biofilms and for controlling bacterial biofilm infections. Such compounds and compositions are also useful in methods for reducing or inhibiting the growth of biofilms and for controlling bacterial biofilm infections involving biofilms.
- -
-
Page/Page column 137-138
(2012/12/13)
-
- N-(Triisopropylsilyl)pyrrole. A Progenitor "Par Excellence" of 3-Substituted Pyrroles
-
A very effective strategy has been devised for the synthesis of 3-substituted pyrroles based on the use of the triisopropylsilyl (TIPS) moiety as a sterically demanding nitrogen substituent to obstruct the attack of electrophilic reagents at the α positions. 1-(Triisopropylsilyl)pyrrole (1) undergoes highly preferential kinetic electrophilic substitution at the β position with a variety of electrophiles (Br+, I+, NO2+, RCO+, etc.) and fluoride ion induced desilylation of the products provides the corresponding 3-substituted pyrroles in good overall yields.Competitive trifluoroacetylation experiments demonstrate that substitution of TIPS-pyrrole at the α positions is decelerated by a factor of >104, vs pyrrole at the same sites, without affecting reactivity at the β positions. 1-(Triisopropylsilyl)-3-bromopyrrole (2) is readily converted into the 3-lithio compound 44 by bromine-lithium interchange with alkyllithium reagents.This previously unavailable, formal equivalent of 3-lithiopyrrole is itself an excellent source of a wide range of β-substituted pyrroles, many of which would not be directly preparable from 1.TIPS-pyrrole can be 3,4-dihalogenated and these compounds undergo sequential halogen-metal interchange trapping reactions.This process is exemplified by an efficient, three-step synthesis of the antibiotic verrucarin E (63) from the dibromo compound (5).
- Bray, Brian L.,Mathies, Peter H.,Naef, Reto,Solas, Dennis R.,Tidwell, Thomas T.,et al.
-
p. 6317 - 6328
(2007/10/02)
-
- Synthesis of New 3-Substituted Pyrroles
-
The synthesis of 3-alkyl- (4), 3-(ω-bromoalkyl)- (5), 3-iodo- (6), 3-formyl- (9a), 3-acetyl-1-(triisopropylsilyl)pyrrole (9b), of 2--2-propanol (7), 1-(triisopropylsilyl)-3-pyrrolecarboxylic acid (8), and 7-heptanoic acid (10) as well as the desilylation of these products to the corresponding 3-substituted pyrroles 11 is described.Intermediates in these syntheses are 1-(triisopropylsilyl)pyrrole (1), 3-bromo- (2), and 3-lithio-1-(triisopropylsilyl)pyrrole (3). - Keywords: Pyrroles, substituted in position 3 / 1-(Triisopropylsilyl)pyrroles, substituted in position 3
- Stefan, Klaus-Peter,Schuhmann, Wolfgang,Parlar, Harun,Korte, Friedhelm
-
p. 169 - 174
(2007/10/02)
-
- 3-Lithiopyrroles by Halogen-Metal Interchange of 3-Bromo-1-(triisopropylsilyl)pyrroles. Synthesis of Verrucarin E and Other 3-Substituted Pyrroles.
-
3-Lithio-1-(trimethylsilyl)pyrrole (7, Scheme 2), obtained by halogen-metal interchange from the 3-bromo compound 2, reacted with various electrophilic reagents to provide products, which on fluoride ion desilylation, gave 3-substituted pyrroles in good overall yields.One such pyrrole 13 (Scheme 3), was converted into 2-formyl-3-octadecylpyrrole (14), reputed to be a metabolite of the marine sponge Oscarella lobularis. 3,4-Dibromo-1-(triisopropylsilyl)pyrrole (5) was efficiently transformed, by a process involving two conscutive bromine-lithium exchange reactions (Scheme 4), into the antibiotic verrucarin E 17.
- Muchowski, Joseph M.,Naef, Reto
-
p. 1168 - 1172
(2007/10/02)
-