Catalytic asymmetric [3 + 3] annulation of cyclopropanes with mercaptoacetaldehyde.
نویسندگان
چکیده
A highly diastereo- and enantioselective [3 + 3] annulation of donor-acceptor cyclopropanes with mercaptoacetaldehyde has been developed. In the presence of a N,N'-dioxide-Sc(iii) complex as the catalyst, a number of aromatic substituted cyclopropyl ketones reacted with mercaptoacetaldehyde smoothly, providing the corresponding chiral tetrahydrothiopyranols in moderate yields with excellent ee (up to 99% ee) and dr values (up to >19 : 1).
منابع مشابه
Lewis acid catalyzed [3 + 2] annulation of ketenimines with donor-acceptor cyclopropanes: an approach to 2-alkylidenepyrrolidine derivatives.
The [3 + 2] annulation reaction of C,C,N-trisubstituted ketenimines with donor-acceptor cyclopropanes bearing aryl, styryl and vinyl substituents at the C2 position, triggered by the Lewis acid Sc(OTf)3, supplies highly substituted pyrrolidines. Activated cyclopropanes fused to naphthalene and [1]benzopyrane nuclei are also suitable substrates in similar transformations, yielding partially satu...
متن کاملCyclization and annulation reactions of nitrogen-substituted cyclopropanes and cyclobutanes.
Cyclization and annulation reactions initiated by ring-opening of small rings, especially cyclopropanes and cyclobutanes are now well-established in synthetic chemistry. Nevertheless, the potential of aminocyclopropanes and cyclobutanes, an important subclass for the synthesis of nitrogen-rich building blocks, has remained unexploited for a long time, despite important pioneering results. In th...
متن کاملDivergent Reactivity of Thioalkynes in Lewis Acid Catalyzed Annulations with Donor-Acceptor Cyclopropanes.
Efficient methods for the convergent synthesis of (poly)cyclic scaffolds are urgently needed in synthetic and medicinal chemistry. Herein, we describe new annulation reactions of thioalkynes with phthalimide-substituted donor-acceptor cyclopropanes, which gave access to highly substituted cyclopentenes and polycyclic ring systems. With silyl-thioalkynes, the Lewis acid catalyzed [3+2] annulatio...
متن کاملDearomatization of electron poor six-membered N-heterocycles through [3 + 2] annulation with aminocyclopropanes.
Many abundant and highly bioactive natural alkaloids contain an indolizidine skeleton. A simple, high yielding method to synthesize this scaffold from N-heterocycles was developed. A wide range of pyridines, quinolines and isoquinolines reacted with donor-acceptor (DA)-aminocyclopropanes via an ytterbium(iii) catalyzed [3 + 2] annulation reaction to give tetrahydroindolizine derivatives. The pr...
متن کاملNucleoside Analogues: Synthesis from Strained Rings
Nucleoside analogues are widely employed as bioactive compounds against cancer and viral infections. Consequently, it is important to develop efficient synthetic methods to access them with high efficiency and structural diversity. Herein, we present a full account of our work on the synthesis of nucleoside analogues via annulations of donor acceptor aminocyclopropanes and aminocyclobutanes. Th...
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:
- Organic & biomolecular chemistry
دوره 14 25 شماره
صفحات -
تاریخ انتشار 2016