Cascade bicyclizations of o-alkynyl aldehydes with thiazolium salts: a new access toward poly-functionalized indeno[2,1-b]pyrroles.
نویسندگان
چکیده
A new cascade bicyclization of o-alkynyl aldehydes with thiazolium salts is described, in which 25 examples of densely functionalized indeno[2,1-b]pyrroles are achieved in a functional-group-compatible manner. Thiazole carbenes generated in situ from thiazolium salts play dual roles as reaction partners and as NHC catalysts. The synthetic utility of these bicyclization reactions results in subsequent C-C bond-forming events to rapidly build up molecular complexity.
منابع مشابه
A novel domino cyclization for the stereoselective synthesis of indeno[2,1-c]pyran and cyclopenta[c]pyran derivatives.
A novel bicyclization of 2-(2-(hydroxymethyl)-1-methylene-2,3-dihydro-1H-inden-2-yl)ethanol with aldehydes in the presence of 10 mol% BF3·OEt2 in dichloromethane at 0-25 °C affords the biologically relevant indeno[2,1-c]pyran scaffolds in good yields with high selectivity. Similarly the bicyclization of 2-(1-(hydroxymethyl)-2-methylenecyclopentyl)ethanol with aldehydes generates the correspondi...
متن کاملThe unprecedented ring transformation from thiazoline-spiro-thiophene to thieno[2,3-b]pyrazine involved in the reaction of 2-thiocarbamoyl thiazolium salts with dimethyl acetylenedicarboxylate.
Reaction of 2-thiocarbamoyl thiazolium salts with dimethyl acetylenedicarboxylate proceeded via a tandem [3+2] cycloaddition and a unprecedented ring transformation to produce functionalized thieno[2,3-b]pyrazine derivatives in good to excellent yields.
متن کاملPhosphine-mediated cascade reaction of azides with MBH-acetates of acetylenic aldehydes to substituted pyrroles: a facile access to N-fused pyrrolo-heterocycles.
One-pot synthesis of substituted pyrroles by a cascade reaction of azides with Morita-Baylis-Hillman acetates of acetylenic aldehydes is described and the reaction is efficiently mediated by triphenyl phosphine at room temperature. Sodium azide is successfully used to provide N-unsubstituted pyrroles, while alkyl azides afforded the corresponding N-alkylated pyrroles through a sequence of allyl...
متن کاملSynthesis of novel polysubstituted N-benzyl-1H-pyrroles via a cascade reaction of alkynyl Fischer carbenes with α-imino glycine methyl esters.
An efficient and simple synthesis of novel and densely substituted N-benzyl-1H-pyrroles 6a-r is described by a 1,4-addition/isomerization/ring closure/demetalation cascade process of alkynyl Fischer carbene complexes 1a-f and 2a and α-imino glycine methyl esters 3a, b, d, g, h, and k promoted with LDA.
متن کاملA New synthesis of functionalized imidazo[2,1-b][1,3]thiazines with thiohydantoins, isocyanides and dialkyl acetylenedicarboxylates
The reaction of stoichiometric amounts of dialkyl acetylenedicarboxylates with alkyl isocyanides and 5,5-diaryl thiohydantoins in toluene and catalytic amount of p-TSA afforded imidazo[2,1-b][1,3]thiazines in good overall yields
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Chemical communications
دوره 51 65 شماره
صفحات -
تاریخ انتشار 2015