Regio- and stereoselective formation of conjugated dienes by titanocene(ii)-promoted alkylation of propargyl carbonates.
نویسندگان
چکیده
Conjugated dienes were produced with complete regio- and stereoselectivity by the titanocene(ii)-promoted alkylation of propargyl carbonates via the formation of 2,3,4-trisubstituted titanacyclobutenes.
منابع مشابه
Regio- and stereoselective synthesis of 1,4-dienes.
Titanocene(II)-promoted cross-coupling between (Z)-alkenyl methyl sulfones and terminal allenes produced 1,4-dienes regioselectively via the formation of 2-alkylidenetitanacyclopentanes. Preferential formation of E,Z-dienes was observed in the reaction using aryl-, amino-, and phosphinylallenes.
متن کاملRegio- and stereoselective anomeric esterification of glucopyranose 1,2-diols and a facile preparation of 2-O-acetylated glucopyranosyl trichloroacetimidates from the corresponding 1,2-diols.
A highly regio- and stereoselective anomeric esterification of 3-O-allyl (or benzyl, or benzoyl)-4,6-O-isopropylidene-alpha,beta-d-glucopyranose with acetyl chloride, or allyl chloroformate, or ethyl chloroformate gave the corresponding 2-OH, 1-beta-acetates or -carbonates in excellent yields. The 2-OH, 1-beta-acetates were readily converted to the corresponding 2-O-acetylated glucopyranosyl tr...
متن کاملNi-catalyzed homoallylation of polyhydroxy n,o-acetals with conjugated dienes promoted by triethylborane.
In the presence of Ni-catalyst and triethylborane, N,O-acetals prepared from glycolaldehyde and glyceraldehyde with primary amines in situ underwent homoallylation with conjugated dienes to provide 2-amino-5-hexenols in high regio- and stereoselectivity. Under similar reaction conditions, N,O-acetals from carbohydrates with primary amines provided the corresponding polyhydroxy-bishomoallylamine...
متن کاملHighly regio- and stereoselective intermolecular tandem reaction to synthesize chloro-substituted 1,3-butadienes.
A palladium catalyzed highly regio- and stereoselective intermolecular tandem reaction of alkynes, CuCl(2) and alkenes by a sequence of chloropalladation/Heck reaction to produce chloro-substituted 1,3-dienes is achieved.
متن کاملA novel catalytic asymmetric route towards skipped dienes with a methyl-substituted central stereogenic carbon.
A highly efficient method for the enantioselective synthesis of 1,4-dienes (skipped dienes) with a methyl-substituted central stereogenic carbon using copper-catalysed asymmetric allylic alkylation of diene bromides was developed. Excellent regio- and enantioselectivity (up to 97 : 3 SN2'/SN2 ratio and 99% ee) were achieved with broad substrate scope.
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 23 شماره
صفحات -
تاریخ انتشار 2009