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Carbon Tetrabromide SPOTLIGHT ██889 SYNLETT Carbonspotlight Tetrabromide Spotlight 429 Compiled by Zhong-Yan Cao This feature focuses on a re- agent chosen by a postgradu- Zhong-Yan Cao was born in Bozhou, P. R. of China, and received ate, highlighting the uses and his B.Sc. from East China Normal University in 2010. Currently he preparation of the reagent in is pursuing his Ph.D. under the supervision of Professor Jian Zhou at the same university. His research interests focus on the develop- current research ment of new catalysts and new methodologies for constructing tetrasubstituted carbon centers. Shanghai Key Laboratory of Green Chemistry and Chemical Pro- cesses, Department of Chemistry, East China Normal University, North Zhongshan Road 3663, Shanghai 200062, P. R. China E-mail: [email protected] Introduction alkenes4 or alkynes5 (Corey–Fuchs reaction). In addition, carbon tetrabromide is a highly efficient catalyst for ver- Carbon tetrabromide, also known as tetrabromomethane, satile reactions, including acylation of phenols, alcohols is a commercially available white solid which is stable at and thiols,6 acetalization and tetrahydropyranylation7 and room temperature and can be easily handled. It is prepared oxidation of aromatic methyl ketones8 or alkenes9 to car- either by the complete bromination of methane or by the boxylic acids under very mild conditions. Carbon tetra- reaction of tetrachloromethane with aluminum bromide. bromide can further promote the synthesis of thioureas In combination with a tertiary phosphine, it has been used and thiuram disulfides.10 Apart from these applications, for the bromination of various functional groups, such as carbon tetrabromide is also used as a crystal growth11 and alcohols (Appel reaction),1 N-heterocycles,2 ethers,3 and chain transfer agent12 in polymer chemistry. for converting aldehydes/ketones into 1,1-dibromo- Abstracts (A) A highly stereoselective synthesis of Z-allyl bromides from Bay- OH CO2Et O CBr , Ph P R lis–Hillman adducts has been realized using CBr4 and Ph3P. The 4 3 CO2Et OAc product can be further elaborated into the natural bioactive fatty acid R CH2Cl2, r.t. R N amides semiplenamides C and E.13 91–99% yield Br H R = Ar, Alk R = C13H27, semiplenamide C R = C15H31, semiplenamide E (B) Selective aerobic photooxidative dibromination of ethyl aromat- CBr4 (2.5 equiv) O ν ics to dibromoacetophenones has been achieved using CBr4, visible O2, h (fluorescent lamp) Br 14 Ar Ar light and molecular oxygen. 48% aq HBr (2.5 equiv), EtOAc 27–74% yield Br (C) CBr4 can participate in atom transfer radical additions to olefins Br [Cu(dap)2Cl] (0.3 mol%) using a visible-light photocatalyst. The 1,1-dibromoalkenes are ob- R + CBr4 CH Cl , LED CBr3 tained after further manipulation.15 2 2 530 R 38–92% yield Br NHBn DBU CBr CBr3 + BnNH 2 Ph 2 THF, r.t., 68% yield Ph This document was downloaded for personal use only. Unauthorized distribution is strictly prohibited. (D) Dong et al. reported the preparation of fully substituted isoxa- HO O zoles from cyclopropyl oximes using a combination of CBr and N N 4 1 16 COR1 R Ph3P as the bromination reagent. 2 CBr4, Ph3P R 2 MeCN, r.t. R CH2CH2Br R1 = Ar, OEt R2 = Me, Ph 75–94% yield SYNLETT 2013, 24, 0889–0890 Advanced online publication: 18.03.20130936-52141437-2096 DOI: 10.1055/s-0032-1318474; Art ID: ST-2013-V0436-V © Georg Thieme Verlag Stuttgart · New York 890 Z.-Y. Cao SPOTLIGHT (E) Chiral 1,3-oxazoline heterocycles bearing fluorinated aliphatic OH O F chains (R ) were obtained from a tandem one-pot reaction promoted CBr4, Ph3P F F R + R CO2H by a combination of CBr4 and Ph3P. The product skeleton is present Et3N, 0–90 °C N Ph NH2 Ph in many bioactive molecules, natural products, organomaterials and 42–65% yield ligands for asymmetric catalysis.17 (F) In the presence of CBr4, dithiocarbamates and thioethers were S S prepared by reaction of dithioic acids, generated in situ, or thiols CBr4, Et3N + NuH Nu with nucleophiles such as active methylene compounds or N-methyl R SH r.t. R S 18 indole at room temperature. R = carbamoyl, Ph, OEt 65–96% yield CBr4, NaOH S RSH + NuH R Nu r.t. to Δ, 28–95% yield R = Alk, Ar (G) Benzoxanthenes owning spectroscopic properties for leuco R dyes, laser technology and fluorescent materials can be prepared us- OH 19 ing CBr4 as the catalyst under solvent-free conditions. + RCHO CBr4 (10 mol%) 130 °C O R = Alk, Ar 81–95% yield References (1) (a) Dyson, B. S.; Burton, J. W.; Sohn, T.; Kim, B.; Bae, H.; (9) Hirashima, S.; Kudo, Y.; Nobuta, T.; Tada, N.; Itoh, A. Kim, D. J. Am. Chem. Soc. 2012, 134, 11781. (b) Lee, J.; Tetrahedron Lett. 2009, 50, 4328. Kim, J. Chem. Mater. 2012, 24, 2817. (10) Liang, F.; Tan, J.; Piao, C.; Liu, Q. Synthesis 2008, 3579. (2) Kijrungphaiboon, W.; Chantarasriwong, O.; Chavasiri, W. (11) Rosokha, S. V.; Vinakos, M. K. Cryst. Growth Des. 2012, Tetrahedron Lett. 2012, 53, 674. 12, 4149. (3) Billing, P.; Brinker, U. H. J. Org. Chem. 2012, 77, 11227. (12) Liu, Y.-Y.; Chen, H.; Ishizu, K. Langmuir 2011, 27, 1168. (4) (a) Arai, N.; Miyaoku, T.; Teruya, S.; Mori, A. Tetrahedron (13) Das, B.; Damodar, K.; Bhunia, N.; Shashikanth, B. Lett. 2008, 49, 1000. (b) Jouvin, K.; Coste, A.; Bayle, A.; Tetrahedron Lett. 2009, 50, 2072. Legrand, F.; Karthikeyan, G.; Tadiparthi, K.; Evano, G. (14) Tada, N.; Ban, K.; Ishigami, T.; Nobuta, T.; Miura, T.; Itoh, Organometallics 2012, 31, 7933. A. Tetrahedron Lett. 2011, 52, 3821. (5) (a) Jacobi, P. A.; Onyango, E. O. J. Org. Chem. 2012, 77, (15) Pirtsch, M.; Paria, S.; Matsuno, T.; Isobe, H.; Reiser, O. 7411. (b) Ni, Z.; Wang, S.; Mao, H.; Pan, Y. Tetrahedron Chem.–Eur. J. 2012, 18, 7336. Lett. 2012, 53, 3907. (c) Liu, J.; Dai, F.; Yang, Z.; Wang, S.; (16) Fu, X.-L.; Huang, P.; Zhou, G.-Y.; Hu, Y.-Q.; Dong, D.-W. Xie, K.; Wang, A.; Chen, X.; Tan, Z. Tetrahedron Lett. Tetrahedron 2011, 67, 6347. 2012, 53, 5678. (d) Zhao, M.; Kuang, C.; Yang, Q.; Cheng, (17) Jiang, H.-Z.; Lu, W.-J.; Cai, Y.-S.; Wan, W.; Wu, S.-X.; X. Tetrahedron Lett. 2011, 52, 992. Zhu, S.-Z.; Hao, J. Tetrahedron 2013, 69, 2150. (6) Zhang, L.; Luo, Y.; Fan, R.; Wu, J. Green Chem. 2007, 9, (18) Tan, J.; Liang, F.-S.; Wang, Y.-M.; Cheng, X.; Liu, Q.; 1022. Yuan, H.-J. Org. Lett. 2008, 10, 2485. (7) Huo, C.; Chan, T. K. Adv. Synth. Catal. 2009, 351, 1933. (19) Raju, B. C.; Pradeep, D. V. S.; Reddy, P. P.; Rao, J. M. Lett. (8) Hirashima, S.; Nobuta, T.; Tada, N.; Itoh, A. Synlett 2009, Org. Chem. 2008, 5, 450. 2017. This document was downloaded for personal use only. Unauthorized distribution is strictly prohibited. Synlett 2013, 24, 889–890 © Georg Thieme Verlag Stuttgart · New York.
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