Catalytic chemoselective [3+3] cycloadditions of azomethine ylides with quinone monoimides leading to the construction of a dihydrobenzoxazine scaffold.
نویسندگان
چکیده
A chemoselective [3+3] cycloaddition of in situ generated azomethine ylides with quinone monoimides has been established, which efficiently led to the construction of dihydrobenzoxazine frameworks with biological relevance, with excellent chemoselectivities and high yields (up to >95 : 5 cr and 98% yield).
منابع مشابه
Diastereo- and enantioselective construction of an indole-based 2,3-dihydrobenzofuran scaffold via catalytic asymmetric [3+2] cyclizations of quinone monoimides with 3-vinylindoles.
The first catalytic asymmetric [3+2] cyclization of quinone monoimides with olefins has been established, which employed 3-vinylindoles as a class of competent olefins and spiro-chiral phosphoric acid as a powerful chiral catalyst, leading to chemo-, diastereo- and enantioselective construction of a biologically important 2,3-dihydrobenzofuran framework with optical purity (up to 99% yield, >95...
متن کاملEnantioselective dearomative [3 + 2] cycloadditions of indoles with azomethine ylides derived from alanine imino esters†
Catalytic, enantioselective [3 + 2] cycloadditions of azomethine ylides derived from alanine imino esters with 3-nitroindoles are reported. The dearomative cycloaddition reactions occur in the presence of a catalyst generated in situ from Cu(OTf)2 and (R)-Difluorphos to form exo’-pyrroloindoline cycloadducts and establish four contiguous stereogenic centers, two of which are fully substituted. ...
متن کاملCatalytic Enantioselective 1,3-Dipolar Cycloadditions of Azomethine Ylides for Biology-Oriented Synthesis
Cycloaddition reactions are among the most powerful methods for the synthesis of complex compounds. In particular, the development and application of the 1,3-dipolar cycloaddition, an important member of this reaction class, has grown immensely due to its powerful ability to efficiently build various five-membered heterocycles. Azomethine ylides are commonly used as dipoles for the synthesis of...
متن کاملIntramolecular [3 + 2]-Cycloadditions of Azomethine Ylides Derived from Secondary Amines via Redox-Neutral C–H Functionalization
Azomethine ylides are accessed under mild conditions via benzoic acid catalyzed condensations of 1,2,3,4-tetrahydroisoquinolines or tryptolines with aldehydes bearing a pendent dipolarophile. These intermediates undergo intramolecular [3 + 2]-cycloadditions in a highly diastereoselective fashion to form polycyclic amines with four new stereogenic centers. Challenging substrates such as piperidi...
متن کاملCatalytic asymmetric [3+2] cycloaddition of azomethine ylides. Development of a versatile stepwise, three-component reaction for diversity-oriented synthesis.
We report a new catalyst system that should enhance the use of enantioselective 1,3-dipolar cycloadditions of azomethine ylides with electronic-deficient olefins in the divergent pathways of diversity-oriented synthesis (DOS). The underlying reaction is of considerable interest in DOS because its stereospecificity enables stereochemical diversification of up to four tetrahedral centers on pyrro...
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 59 شماره
صفحات -
تاریخ انتشار 2015