Reactions of Alkenes: The Kutsumura/Saito synthesis of Aplysinoplide B
Gerhard Hilt of Philipps-Universitšt Marburg developed (Org. Lett. 2015, 17, 2952. DOI: 10.1021/acs.orglett.5b01230) a Ni catalyst for the kinetic isomerization of a terminal alkene 1 to the Z internal alkene 2. Paul J. Chirik of Princeton University established (Org. Lett. 2015, 17, 2716. DOI: 10.1021/acs.orglett.5b01135) conditions for the equilibrating conversion of the alkene 3 to the benzylic boronate 4. Phil S. Baran of Scripps/La Jolla described (Science 2015, 348, 886. DOI: 10.1126/science.aab0245) a protocol for the Markovnikov amination of an alkene 5 to give the amine 6. Koji Hirano and Masahiro Miura of Osaka University showed (J. Am. Chem. Soc. 2015, 137, 6460. DOI: 10.1021/jacs.5b02775) that with the proper choice of Cu catalyst, an alkene 7 could be converted cleanly into either the amino boronate 8 or its regioisomer. Ning Jiao of Peking University devised (J. Am. Chem. Soc. 2015, 137, 6059. DOI: 10.1021/jacs.5b02347) a procedure for converting an alkene 9 to the azido alcohol 10.
Izabella Jastrzebska and Jacek W. Morzycki of the University of Bialystok employed (J. Org. Chem. 2015, 80, 6052. DOI: 10.1021/acs.joc.5b00410) benzeneselenic anhydride to oxidize the alkene 11 to the unsaturated aldehyde 12. Under the same conditions, internal alkenes were converted to the diols.
Naohiko Yoshikai of Nanyang Technological University used (ACS Catal. 2015, 5, 3054. DOI: 10.1021/acscatal.5b00581) the imine 13 to effect the hydroacylation of the alkene 12, leading to the ketone 14. Zhong-Quan Liu of Lanzhou University added (Chem. Commun. 2015, 51, 9969. DOI: 10.1039/C5CC02968F) acetonitrile to the alkene 15 under free radical conditions to give the nitrile 16. Jianlin Han of Nanjing University devised (Org. Lett. 2015, 17, 1160. DOI: 10.1021/acs.orglett.5b00088) a general procedure for the regioselective addition of primary and secondary alcohols to alkenes, as illustrated by the conversion of 17 to 18. David W. C. MacMillan of Princeton University prepared (Nature 2015, 519, 74. DOI: 10.1038/nature14255) 22 by adding 1,4-dicyanobenzene 21 to the alkene 20 under photoredox conditions. Guosheng Liu of the Shanghai Institute of Organic Chemistry converted (J. Am. Chem. Soc. 2015, 137, 2480. DOI: 10.1021/jacs.5b00719) the alkene 3 to the β-amino acid derivative 25 by Pd-catalyzed carbonylation in the presence of phthalimide 24.
Building on the work of Zard and Renaud, Yannick Landais of the University of Bordeaux devised (Org. Lett. 2015, 17, 1958. DOI: 10.1021/acs.orglett.5b00672) a class of reagents exemplified by 26. Under catalytic free radical conditions, addition to the alkene 7 led to the oxime 27 via the formation of two C-C bonds.
Continuing their work on the bromination/dehydrobromination of alkenes ( 2011, September 19; 2012, May 21), Noriki Kutsumura of the University of Tsukuba and Takao Saito of the Tokyo University of Science observed (Tetrahedron Lett. 2015, 56, 2602. DOI: 10.1016/j.tetlet.2015.04.010) remarkable regio- and sterocontrol in the conversion of 28 to 29. This specific trisubstituted alkene construction enabled the total synthesis of Aplysinoplide B (30).