meso-Phbox-Pd(II) catalyzed tandem carbonylative cyclization of 1-ethynyl-1-propargyl acetate.
نویسندگان
چکیده
Palladium(II) catalyzed carbonylation of 1-ethynyl-1-propargyl acetate is described; in the absence of the bisoxazoline (box) ligand, the second triple bond did not react, affording cyclic orthoesters and . The use of meso-Phbox-Pd(ii) strikingly changed the course of the reaction, yielding bicyclic lactone by tandem carbonylative cyclization as a result of insertion of the second triple bond.
منابع مشابه
Cyclization-carbonylation-cyclization coupling reaction of propargyl ureas with palladium(II)-bisoxazoline catalyst.
The cyclization-carbonylation-cyclization coupling reaction (CCC-coupling reaction) of propargyl ureas catalyzed by Pd(II)(box) complexes afforded symmetrical ketones bearing two 2-amino-2-oxazoline groups in good to moderate yields.
متن کاملGold-catalyzed cyclization of allenyl acetal derivatives
The gold-catalyzed transformation of allenyl acetals into 5-alkylidenecyclopent-2-en-1-ones is described. The outcome of our deuterium labeling experiments supports a 1,4-hydride shift of the resulting allyl cationic intermediates because a complete deuterium transfer is observed. We tested the reaction on various acetal substrates bearing a propargyl acetate, giving 4-methoxy-5-alkylidenecyclo...
متن کاملSynthesis of multi-substituted pyrroles using enamides and alkynes catalyzed by Pd(OAc)2 with molecular oxygen as an oxidant.
A cyclization reaction between enamides and alkynes catalyzed by palladium(II) acetate is described. In this method, the molecular oxygen serves as an efficient oxidant for the Pd(II)/Pd(0) catalytic cycle. The simple reaction conditions permit this methodology to be used as a general tool for the preparation of multi-substituted pyrroles.
متن کاملCopper-catalyzed decarboxylative cyclization via tandem C-P and C-N bond formation: access to 2-phosphorylmethyl indoles.
A novel copper-catalyzed decarboxylative cyclization of ethynyl benzoxazinanones with P(O)H compounds has been developed. This protocol leads to a series of 2-phosphorylmethyl indoles with high efficiency and selectivity (up to 99% yield) through tandem C-P/C-N bond formation under mild conditions.
متن کاملA convenient and general palladium-catalyzed carbonylative coupling for the synthesis of 2-arylbenzoxazinones.
Benzoxazinones represent a class of annulated nitrogen heterocycles that are of interest to organic synthesis owing to their various biological activities. Among the different methodologies developed for their preparation, cyclization of anthranilic acid, N-acylanthranilic acid, or isotonic anhydride are most accepted. Although alternative methodologies are known, the availability of substrates...
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 31 شماره
صفحات -
تاریخ انتشار 2008