A general synthesis of dihydrobenzofurans by intramolecular conjugate addition

نویسندگان
چکیده

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Asymmetric Synthesis of Multisubstituted Dihydrobenzofurans by Intramolecular Conjugate Addition of Short-Lived C-O Axially Chiral Enolates.

Enantioselective intramolecular conjugate addition reactions of short-lived C-O axially chiral enolates have been developed. The reactions proceeded with inversion of the configuration and provided dihydrobenzofurans with contiguous tetra- and trisubstituted carbon centers in up to 96% enantiomeric excess (ee).

متن کامل

Stereodivergent Organocatalytic Intramolecular Michael Addition/Lactonization for the Asymmetric Synthesis of Substituted Dihydrobenzofurans and Tetrahydrofurans

A stereodivergent asymmetric Lewis base catalyzed Michael addition/lactonization of enone acids into substituted dihydrobenzofuran and tetrahydrofuran derivatives is reported. Commercially available (S)-(-)-tetramisole hydrochloride gives products with high syn diastereoselectivity in excellent enantioselectivity (up to 99:1 d.r.syn/anti , 99 % eesyn ), whereas using a cinchona alkaloid derived...

متن کامل

Asymmetric synthesis of carbocycles: use of intramolecular conjugate displacement.

Intramolecular conjugate displacement (ICD), the process illustrated in , has been applied to the Morita-Baylis-Hillman adducts formed from (5S)-5-(l-menthyloxy)-2(5H)-furanone and aldehydes that are substituted in the γ- or δ-position by geminal phenylthio groups. When the initial Morita-Baylis-Hillman alcohols are acetylated and oxidized to geminal sulfones, deprotonation causes ring closure ...

متن کامل

Aldol condensation versus conjugate addition: intramolecular cyclization using a combination of Lewis acid and 1,2-diol.

The reactivity of 3-substituted 4-methyl-4-(3-oxobutyl)-2-cyclohexen-1-ones (1) in the presence of a combination of a Lewis acid and a 1,2-diol was studied. The results suggest several factors that influence 6-membered ring formation, including two types of intramolecular aldol reaction and intramolecular 1,4-addition, due to the C3-substituent, Lewis acid, and the presence of diol. In this stu...

متن کامل

Intramolecular Michael addition reaction for the synthesis of benzylbutyrolactones.

A convenient synthesis of benzyl-gamma-butyrolactone derivatives via intramolecular Michael addition reaction of nitro-substituted aryl allyl beta-ketocarboxylates is reported. The method features simple operation, mild reaction conditions and high efficiency.

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Canadian Journal of Chemistry

سال: 1987

ISSN: 0008-4042,1480-3291

DOI: 10.1139/v87-335