1,1-Alkenylboration of diarylphosphino-enynes: convenient synthetic entry to vicinal P/B Lewis pairs at extended conjugated π-frameworks.
نویسندگان
چکیده
Alkenylboranes R-CH=CH-B(C6F5)2 undergo carbon-carbon coupling by means of 1,1-alkenylboration with diarylphosphino-enynes to give substituted conjugated hexatriene derivatives that bear a vicinal pair of B(C6F5)2 Lewis acid and PAr2 Lewis base functionalities at their central carbon portions. A series of six examples was prepared and all compounds were characterized by X-ray diffraction. Consecutive reactions of two selected examples were carried out.
منابع مشابه
Reaction of strongly electrophilic alkenylboranes with phosphanylalkynes: rare examples of intermolecular 1,1-alkenylboration reactions.
Simple alkenylbis(pentafluorophenyl)boranes undergo 1,1-alkenylboration with phosphanylacetylenes to give phosphane-borane Lewis pairs with a conjugated diene backbone.
متن کاملIntramolecular frustrated lewis pairs: formation and chemical features.
Intramolecular vicinal and geminal frustrated Lewis pairs (FLPs) featuring bulky substituents at phosphorus or nitrogen and strongly electron-withdrawing bulky pentafluorophenyl substituents at boron undergo a variety of addition and/or activation reactions with small molecules. A number of examples of such reactions are presented and discussed, among them the FLP activation of dihydrogen to gi...
متن کاملFacile 1,1-Carboboration Reaction of a Diarylphosphino-substituted Conjugated Diyne with Tris(pentafluorophenyl)borane
Dedicated to Professor Heinrich Nöth on the occasion of his 85th birthday Bis(dimesitylphosphanyl)butadiyne (14) reacts with B(C6F5)3 by a 1,1-carboboration sequence. The selective attack at a single phosphanyl-alkyne moiety is observed. First a phosphirenium-borate zwitterion 15 is formed at r. t. Thermolysis (80 ◦C) results in the E-selective formation of the 1,1carboboration product, the fru...
متن کامل4,4-Bis(4-methylphenylsulfanyl)-1,1-diphenyl-2-azabuta-1,3-diene
In the title compound, C(29)H(25)NS(2), both the Cl atoms of the aza-diene precursor 4,4-dichloro-1,1-diphenyl-2-aza-buta-1,3-diene are replaced by two vicinal S-p-tolyl substituents attached to the terminal C atom of a π-conjugated 2-aza-butadiene array. The aza-diene chain is planar to within 0.01 Å. One of the phenyl rings seems to be slightly π-conjugated with the aza-diene core [dihedral a...
متن کاملRing-Closing Metathesis with Vicinal Dibromoalkenes as Protected Alkynes: A Synthetic Approach to Macrocyclic Enynes.
A new strategy to access macrocyclic enynes was developed. To block undesired ene-yne cyclization pathways, alkynes were protected via bromination and the resultant acyclic vic-(E)-dibromotrienes participated in selective ene-ene ring closing metathesis reactions. Zinc-promoted deprotection of (E)-dibromodienes provided macrocyclic enynes in high yields.
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 13 3 شماره
صفحات -
تاریخ انتشار 2015