Synthesis of 3,4-benzo-7-hydroxy-2,9-diazabicyclo[3.3.1]non-7-enes by cyclization of 1,3-bis(silyl enol ethers) with quinazolines.
نویسندگان
چکیده
A variety of functionalized 3,4-benzo-7-hydroxy-2,9-diazabicyclo[3.3.1]non-7-enes were prepared by one-pot cyclizations of 1,3-bis(silyl enol ethers) with quinazolines. The mechanism of the cyclization was studied by B3LYP/6-31G(d) density functional theory computations. The products could be functionalized by Suzuki cross-coupling reactions. The reaction of 1,3-bis(silyl enol ethers) with phthalazine afforded open-chain rather than cyclization products.
منابع مشابه
Silyl Enol Ether Prins Cyclization: Diastereoselective Formation of Substituted Tetrahydropyran-4-ones
A diastereoselective synthesis of cis-2,6-disubstituted tetrahydropyran-4-ones was developed. The key step of this methodology, a silyl enol ether Prins cyclization, was promoted by a condensation reaction between a hydroxy silyl enol ether and an aldehyde to afford substituted tetrahydropyran-4-ones. The cyclization was tolerant of many functional groups, and the modular synthesis of the hydro...
متن کاملOne-pot synthesis of tropinone by tandem (domino) ene-type reactions of acetone silyl enol ethers.
A synthetic approach for tropane alkaloids on the basis of tandem (domino) ene-type reactions of acetone silyl enol ethers with iminium ions is shown to be triggered by intermolecular ene-type reactions followed by 6-(2,5) silatropic ene-type cyclizations.
متن کاملSynthesis and characterization of novel silyl derivatives of curcumin
Abstract:Turmeric is a member of the ginger family (Zingiberaceae), which is extensively used as a spice, food preservative and colouring material. Curcumin is a main bioactive natural compound derived from the rhizome of this plant. Curcumin can exist in several tautomeric forms, keto and enol. The keto form is more stable than enol form. Silyl ethers have proven to be versatile substrates for...
متن کاملPalladium-catalyzed enantioselective cyclization of silyloxy-1,6-enynes.
Transition-metal-catalyzed cycloisomerization and cyclization reactions of enynes have emerged as powerful methods for the construction of heteroand carbocyclic compounds.1 More recently, enantioselective cycloisomerization of 1,6and 1,7-enynes has been employed in the preparation of enantioenriched 1,4-diene containing structures.2-4 Despite its potential utility, the related enantioselective ...
متن کاملSynthesis of 2-substituted 7-hydroxybenzofuran-4-carboxylates via addition of silyl enol ethers to o-benzoquinone esters.
Mukaiyama Michael addition of silyl enol ethers 13 to the 1,2-quinone-4-carboxylate 6 (formed in situ by oxidation of the catechol ester 8) afforded the 2-subsituted 7-hydroxybenzofuran-4-carboxylates 14 in fair to good yields. Alkyl and aryl systems work well, but highly electron-rich silyl enol ethers could not be used because of competing oxidation.
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 6 16 شماره
صفحات -
تاریخ انتشار 2008