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Chemfile Vol.7 No 7 2007 VOLUME 7 NUMBER 7 Product Directory Boron Reagents for Suzuki Coupling BORYLATION REAGENTS BORONIC ACIDS BORONATE ESTERS TRIFLUOROBORATE SALTS Potassium cyclopropyltrifluoroborate: a simple reagent for the introduction of a cyclopropyl group via Suzuki cross–coupling. sigma-aldrich.com Table of Contents Sigma-Aldrich is committed to providing the most extensive portfolio of high-quality boronic acids, boronate esters, and trifluoroborate salts for use in Suzuki coupling, and we continually expand our product listing. Within each section of this directory, products are listed by increasing molecular formula. If you are unable to find a coupling reagent for your research, “Please Bother Us” at nwallock@sial.com, or contact your local Sigma-Aldrich office (see back cover). If viewing the electronic version, simply select from the category below to jump to that section or activate your Adobe® Bookmarks. You may also search by name, product number, molecular formula, or CAS registry number by using the “find” feature in Adobe® (Ctrl+F in Windows® or Command+F in a Macintosh® environment). Borylation Reagents Boronate Esters Trifluoroborate Salts Introduction Boronic Acids Alkylboronate esters Alkyltrifluoroborates Alkylboronic acids Alkenylboronate esters Alkenyltrifluoroborates Alkenylboronic acids Allenyl- and Alkynylboronate esters Aryltrifluoroborates Arylboronic acids Arylboronate esters S-Heteroaryltrifluoroborates N-Heteroarylboronic acids N-Heteroarylboronate esters O-Heteroarylboronic acids O-Heteroarylboronate esters S-Heteroarylboronic acids S-Heteroarylboronate esters Foreword Akira Suzuki Professor Emeritus, Hokkaido University Sapporo, Japan Reactions in which new carbon–carbon bonds are formed are key steps in building the complex, bioactive molecules that become developed into drugs and agrochemicals. These reactions are also vital in developing the new generation of ingeniously designed organic materials with novel electronic, optical, or mechanical properties, that are likely to play a significant role in the burgeoning area of nanotechnology. During the past 40 years, the most important carbon–carbon bond-forming methodologies have involved the use of transition metals to mediate the reactions in a controlled and selective manner. Perhaps the most widely used of these chemistries is the cross-coupling reaction of various organoboron compounds with organic electrophiles catalyzed by a palladium complex. This reaction, Suzuki coupling, is now regarded as an integral part of innumerable synthetic routes used to build complex organic chemicals. Suzuki coupling has many advantages. The reactants are readily available, nontoxic, and air- and water-stable. They react under mild conditions and are amenable to a variety of reaction conditions, including the use of aqueous solvents and substrate supports. The inorganic boron byproducts can be easily removed after completion of the reaction. Most important of all, the coupling proceeds with high regio- and stereoselectivity, and is little affected by steric hindrance. It does not affect other functional groups in the The Suzuki Coupling Reaction molecule, and can be used in one-pot strategies. R BYn PdLn The reaction has proved to be extremely + R R versatile. It was first carried out between Base alkenyl reactants, but over the years, R X the scope of the reaction has been - extended to couple carbon atoms in Yn = (OH)2, (OR)2, F3 , R2 aryl, alkyl, and alkynyl groups under a X = halide, OTf, N + wide variety of conditions. Thus, the 2 Suzuki coupling reaction is truly “carbon–carbon bond formation made easy.” TO ORDER: Contact your local Sigma-Aldrich office (see back cover), sigma-aldrich.com or visit sigma-aldrich.com/chemicalsynthesis. Borylation Reagents 4,4,5,5-Tetramethyl-1,,-dioxaborolane, Bis(pinacolato)diboron Bis(diethyl-L-tartrate glycolato)diboron CH O O sold by volume 4794 3 CH3 57165 H C CH H3C O O CH3 3 O O 3 CH B B O O 45646 3 C12H24B2O4 C16H24B2O12 B B H C O H3C O O CH3 3 H C O O O O B H CH3 CH3 3 Pinacolborane MW: 253.94 MW: 429.98 CH3 H3C O O O CH C6H13BO2 3 [73183-34-3] [480438-20-8] MW: 127.98 D [25015-63-8] Bis(hexylene glycolato)diboron Bis(diisopropyl- -tartrate glycolato)- Borylation Reagents CH3 CH 55685 H C 3 diboron 3 O O BB CH H C 4,4,5,5-Tetramethyl-1,,-dioxaborolane, C12H24B2O4 5717 3 O O 3 O O CH3 H C CH H C 3 O O 3 sold by weight MW: 253.94 3 CH3 C20H32B2O12 O O B B 655856 CH3 [230299-21-5] MW: 486.08 H C O O O O 3 CH H3C O 3 B H CH O O Pinacolborane [480438-21-9] 3 H3C H3C O CH Bis(catecholato)diboron C6H13BO2 3 4786 O O Bis(diisopropyl-L-tartrate MW: 127.98 B B O O [25015-63-8] C12H8B2O4 glycolato)diboron MW: 237.81 CH H C 57181 3 O O 3 H3C CH3 4,4,5,5-Tetramethyl-1,,-dioxaborolane [13826-27-2] C20H32B2O12 O O O O B B solution, 1.0 M in tetrahydrofuran MW: 486.08 H3C O O O O CH3 CH Bis[(+)-pinanediolato]diboron CH O O 458945 3 [230299-10-2] 3 H3C H C O 3 H CH B H 5710 3 Pinacolborane O O H C O 3 B B CH C20H32B2O4 Bis(N,N,N’,N’-tetramethyl-D-tartaramide C6H13BO2 3 O O MW: 127.98 MW: 358.09 CH3 H glycolato)diboron [230299-17-9] O O [25015-63-8] 570 H3C CH3 N O O N H C CH C16H28B2N4O8 3 B B 3 H C Catecholborane solution, 1.0 M in Bis[(–)-pinanediolato]diboron 3 N O O N CH3 MW: 426.04 H C CH H 3 O O 3 57149 CH3 tetrahydrofuran O O [230299-42-0] C H B O B B 576 O 20 32 2 4 O O B H CH3 H O MW: 358.09 Bis(N,N,N’,N’-tetramethyl-L-tartaramide C6H5BO2 MW: 119.91 [230299-05-5] glycolato)diboron O O [274-07-7] 578 H3C CH3 D N O O N Bis(diethyl- -tartrate glycolato)diboron H C CH C16H28B2N4O8 3 B B 3 H C Bis(neopentyl glycolato)diboron 57157 O O 3 N O O N CH3 H3C CH3 MW: 426.04 H C CH O O O O 3 O O 3 O O C16H24B2O12 B B 518808 H3C CH3 [480438-22-0] BB O O H C CH H3C O O 3 O O 3 MW: 429.98 CH3 C10H20B2O4 O O MW: 225.89 [312693-46-2] [201733-56-4] Boronic Acids Alkylboronic acids Methylboronic acid Butylboronic acid -Methyl-1-butylboronic acid OH OH CH3 1656 1644 H3C B 655090 H C B OH 3 OH CH BO OH C H BO C H BO H3C B 5 2 4 11 2 5 13 2 OH MW: 59.86 MW: 101.94 MW: 115.97 [13061-96-6] [4426-47-5] [98139-72-1] Cyclopropylboronic acid (-Methylpropyl)boronic acid Cyclohexylboronic acid OH H C OH OH 597988 465 3 B 556580 B B OH CH3 OH OH C3H7BO2 C4H11BO2 C6H13BO2 MW: 85.90 MW: 101.94 MW: 127.98 [411235-57-9] [84110-40-7] [4441-56-9] Isopropylboronic acid Cyclopentylboronic acid Phenethylboronic acid 648787 CH3 588415 OH 5884 OH OH B B C H BO H3C B C H BO OH C H BO OH 3 9 2 OH 5 11 2 8 11 2 MW: 87.91 MW: 113.95 MW: 149.98 [80041-89-0] [63076-51-7] [34420-17-2] sigma-aldrich.com Cyclobutylboronic acid Neopentylboronic acid 8 646598 OH 68671 OH B B OH OH C4H9BO2 C5H13BO2 MW: 99.92 MW: 115.97 [849052-26-2] [701261-35-0] Ready to scale up? For competitive quotes on larger quantities or custom synthesis, contact your local Sigma-Aldrich office, or visit safcglobal.com. 4 Alkenylboronic acids trans--Chloromethylvinylboronic acid trans--(4-Chlorophenyl)vinylboronic acid trans--(4-(Trifluoromethyl)phenyl)- 556599 OH 5569 OH vinylboronic acid Cl B B C H BClO OH C H BClO OH 5190 OH 3 6 2 8 8 2 B Cl OH MW: 120.34 MW: 182.41 C9H8BF3O2 [215951-86-3] [154230-29-2] MW: 215.96 F3C [352525-91-8] cis-1-Propene-1-boronic acid trans--(-Fluorophenyl)vinylboronic acid 57179 CH3 OH 67971 OH trans--(4-Methylphenyl)vinylboronic B B OH OH C3H7BO2 C8H8BFO2 acid OH MW: 85.90 MW: 165.96 F 56819 B OH [7547-96-8] [849062-22-2] C9H11BO2 MW: 161.99 H3C trans-1-Propen-1-ylboronic acid trans--(4-Fluorophenyl)vinylboronic acid [72316-17-7] 57668 OH 51897 OH B B H3C OH OH C3H7BO2 C8H8BFO2 trans--Phenyl-1-propen-1-ylboronic acid F MW: 85.90 MW: 165.96 64606 OH B OH [7547-97-9] [214907-24-1] C9H11BO2 MW: 161.99 trans--Buten--ylboronic acid trans--Phenylvinylboronic acid [129423-29-6] Boronic Boronic Acids 68056 CH3 OH 47790 OH B B H OH OH C4H9BO2 C8H9BO2 trans--(4-Methoxyphenyl)vinylboronic CH3 MW: 99.92 MW: 147.97 acid [125261-72-5] [6783-05-7] 518980 OH B OH C9H11BO3 -Methyl--buten--ylboronic acid 1-Phenylvinylboronic acid MW: 177.99 H3CO 69079 CH3 OH 57150 OH B B [72316-18-8] H3C OH OH C5H11BO2 C8H9BO2 CH3 MW: 113.95 MW: 147.97 trans-1-Nonenylboronic acid [870777-16-5] [14900-39-1] 57994 OH B H3C OH C9H19BO2 trans-1-Penten-1-ylboronic acid trans--Cyclohexylvinylboronic acid MW: 170.06 57845 OH 59656 OH B B [57404-77-0] H3C OH OH C5H11BO2 C8H15BO2 MW: 113.95 MW: 154.01 Vinylboronic anhydride pyridine complex [104376-24-1] [37490-33-8] 67998 B C11H14B3NO23 O O • trans-1-Heptenylboronic acid trans-1-Octen-1-ylboronic acid B B N MW: 240.67 O 57986 OH 5107 OH B H3C B [442850-89-7] H3C OH OH C7H15BO2 C8H17BO2 MW: 142.00 MW: 156.03 trans--(4-Biphenyl)vinylboronic acid [42599-16-6] 56045 OH B OH C14H13BO2 MW: 224.06 [352530-23-5] Arylboronic acids 4-Bromo-,,5,6-tetrafluorophenylboronic ,,4,6-Tetrafluorophenylboronic 8 -Bromo-,6-difluorophenylboronic acid acid acid 5574 F OH B F OH F OH OH 59966 68061 C6H4BBrF2O2 F B B OH OH F C6H2BBrF4O2 C6H3BF4O2 MW: 236.81 Br Br F F F MW: 272.79 F MW: 193.89 F [352535-84-3] [511295-00-4] Phenyl-d5-boronic acid 6-Bromo-,-difluorophenylboronic acid 517860 D OH 6-Bromo--fluoro--iodophenyl- 8 65774 Br OH D B B OH OH C6H2BD5O2 boronic acid C6H4BBrF2O2 MW: 126.96 D D 66679 Br OH MW: 236.81 F D B F OH [215527-70-1] C6H4BBrFIO2 [870718-10-8] F MW: 344.71 I Pentafluorophenylboronic acid -Bromo-4,5-difluorophenylboronic acid 465097 F OH 4-Bromo-,6-difluorophenylboronic acid 64581 OH F B F B OH 55718 F OH C H BBrF O OH C6H2BF5O2 B 6 4 2 2 F F OH F Br MW: 211.88 F C6H4BBrF2O2 MW: 236.81 [1582-24-7] MW: 236.81 Br F [849062-34-6] TO ORDER: Contact your local Sigma-Aldrich office (see back cover), sigma-aldrich.com or visit sigma-aldrich.com/chemicalsynthesis.
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