Best Synthetic Methods: Reduction

State University ◽

University Of Texas ◽

Ru Catalyst ◽

Reaction Matrix ◽

National University ◽

Jaiwook Park of Pohang University of Science and Technology has developed (Org. Lett. 2007, 9, 3417) a procedure for the preparation of Pd-impregnated magnetic Fe nanoparticles. This effective hydrogenation catalyst was attracted to an external magnet and so was easily separated from the reaction matrix. Duk Keun An of Kangwon National University has found (Chem. Lett. 2007, 36, 886) that by including NaOtBu, Dibal reduction of an ester such as 3 can be made to reliably stop at the aldehyde 4. By using the easily-prepared pentaﬂurophenyl ester 5, Panagiota Moutevelis-Minakakis of the University of Athens was able to reduce an acid to the alcohol 6. Lionel A. Saudan of Firmenich SA, Geneva has devised (Angew. Chem. Int. Ed. 2007, 46, 7473) a Ru catalyst that will hydrogenate an ester such as 7 to the alcohol 8 without reducing an internal alkene. Norio Sakai of the Tokyo University of Science has established (J. Org. Chem. 2007, 72, 5920) what promises to be a general route to ethers 10, by direct reduction of the corresponding ester 9. Hideo Nagashima of Kyushu University has developed ( Chem. Commun. 2007, 4916) a Ru catalyst that effected selective hydrogenation of an amide 11 to the amine 12 without reducing ketones or esters. Alternatively, Jason S. Tedrow of Amgen Inc., Thousand Oaks, CA has found (J. Org. Chem. 2007, 72, 8870) that a protocol developed by Robert E. Maleczka, Jr. of Michigan State University was effective for reducing an aryl ketone 13 to the corresponding hydrocarbon 14 without reducing the amide. The stereocontrolled reductive amination of cyclic ketones such as 15 has been a continuing challenge. Shawn Cabral of Pfizer, Inc. in Groton, CT has reported (Tetrahedron Lett. 2007, 48, 7134) complementary reagent combinations, leading selectively to either 16 or 17. To control catalytic hydrogenation, it is often desirable to control the H2 supply. John S. McMurray of the University of Texas M. D. Anderson Cancer Center in Houston has shown (J. Org. Chem. 2007, 72, 6599) that Et3SiH is a convenient H2 source. Nitro alkanes add to aldehydes to give nitro alkenes such as 20.

Arrays of Stereogenic Centers: The Davies Synthesis of Acosamine

Organic Synthesis ◽

10.1093/oso/9780190200794.003.0041 ◽

2015 ◽

Author(s):

Douglass F. Taber

Keyword(s):

Conjugate Addition ◽

State University ◽

One Pot ◽

Relative Configuration ◽

University Of Texas ◽

Stereogenic Centers ◽

National University ◽

The University ◽

Mediated Oxidation

Babak Borhan of Michigan State University found (Angew. Chem. Int. Ed. 2011, 50, 2593) that the ligand developed for asymmetric osmylation worked well for the enantioselective cyclization of 1 to 2. Kyungsoo Oh of IUPUI devised (Org. Lett. 2011, 13, 1306) a Co catalyst for the stereocontrolled addition of 4 to 3 to give 5. Michael J. Krische of the University of Texas Austin prepared (Angew. Chem. Int. Ed. 2011, 50, 3493) 8 by Ir*-mediated oxidation/addition of 7 to 6. Yixin Lu of the National University of Singapore employed (Angew. Chem. Int. Ed. 2011, 50, 1861) an organocatalyst to effect the stereocontrolled addition of 10 to 9. Naoya Kumagai and Masakatsu Shibasaki of the Institute of Microbial Chemistry, Tokyo took advantage (J. Am. Chem. Soc. 2011, 133, 5554) of the soft Lewis basicity of 13 to effect stereocontrolled condensation with 12. Yujiro Hayashi of the Tokyo University of Science found (Angew. Chem. Int. Ed. 2011, 50, 2804, not illustrated) that aqueous chloroacetaldehyde participated well in crossed aldol condensations. Andrew V. Malkov, now at Loughborough University, and Pavel Kocovsky of the University of Glasgow showed (J. Org. Chem. 2011, 76, 4800) that the inexpensive mixed crotyl silane 16 could be added to 15 with high stereocontrol. Shigeki Matsunaga of the University of Tokyo and Professor Shibasaki opened (J. Am. Chem. Soc. 2011, 133, 5791) the meso aziridine 18 with malonate 19 to give 20. Masahiro Terada of Tohoku University effected (Org. Lett. 2011, 13, 2026) the conjugate addition of 22 to 21 with high stereocontrol. Jinxing Ye of the East China University of Science and Technology reported (Angew. Chem. Int. Ed. 2011, 50, 3232, not illustrated) a related conjugate addition. Kian L. Tian of Boston College observed (Org. Lett. 2011, 13, 2686) that the kinetic hydroformylation of 24 set the relative configuration of two stereogenic centers. Alexandre Alexakis and Clément Mazet of the Université de Genève established (Angew. Chem. Int. Ed. 2011, 50, 2354) a tandem one-pot procedure for the addition of 26 to 27 to give 28.

Reviewer Acknowledgements

Journal of Education and Training Studies ◽

10.11114/jets.v6i1.2908 ◽

2017 ◽

Vol 6 (1) ◽

pp. 169

Author(s):

Robert Smith

Keyword(s):

Education And Training ◽

Economic Research ◽

State University ◽

American University ◽

Kwazulu Natal ◽

National University ◽

The University ◽

And Training

Journal of Education and Training Studies (JETS) would like to acknowledge the following reviewers for their assistance with peer review of manuscripts for this issue. Many authors, regardless of whether JETS publishes their work, appreciate the helpful feedback provided by the reviewers. Their comments and suggestions were of great help to the authors in improving the quality of their papers. Each of the reviewers listed below returned at least one review for this issue.Reviewers for Volume 6, Number 1Brenda L. Shook, National University, USACagla Atmaca, Pamukkale University, TurkeyCarole Fern Todhunter, The University of Nottingham, UKCharlotte Alverson, University of Oregon, USAChosang Tendhar, Long Island University (LIU), USAEnisa Mede, Bahcesehir University, TurkeyErica D. Shifflet-Chila, Michigan State University, USAGreg Rickwood, Nipissing University, CanadaHyesoo Yoo, Virginia Tech., USAIoannis Syrmpas, University of Thessaly, GreeceJohn Cowan, Edinburgh Napier University, UKLinda J. Rappel, Yorkville University/University of Calgary, CanadaMan-fung Lo, The Hong Kong Polytechnic University, Hong KongMassimiliano Barattucci, Ecampus University, ItalyMaurizio Sajeva, Pellervo Economic Research PTT, FinlandMehmet Inan, Marmara University, TurkeyMichail Kalogiannakis, University of Crete, GreeceMin Gui, Wuhan University, ChinaNerina Fernanda Sarthou, Universidad Nacional del Centro de la Provincia de Buenos Aires, ArgentinaPirkko Siklander, University of Lapland, FinlandRichard H. Martin, Mercer University, USARichard Penny, University of Washington Bothell, USARiyadh Tariq Kadhim Al-Ameedi, Babylon University, IraqRufaidah Kamal Abdulmajeed, Baghdad University, IraqSadia Batool, Preston University Islamabad, PakistanSelloane Pitikoe, University of Kwazulu-Natal, South AfricaSenem Seda Şahenk Erkan, Marmara University, TurkeySeyyedeh Mina Hamedi, Ferdowsi University of Mashhad, IranSisi Chen, American University of Health Sciences, USATilanka Chandrasekera, Oklahoma State University, USAYalçın Dilekli, Aksaray University, TurkeyYerlan Seisenbekov, Kazakh National Pedagogical University, KazakhstanYi Lu, American Institute for Research, USAYuChun Chen, Louisiana Tech University, USARobert SmithEditorial AssistantOn behalf of,The Editorial Board of Journal of Education and Training StudiesRedfame Publishing9450 SW Gemini Dr. #99416Beaverton, OR 97008, USAURL: http://jets.redfame.com

Transition Metal-Mediated Ring Construction: The Yu Synthesis of 1-Desoxyhypnophilin

Organic Synthesis ◽

10.1093/oso/9780199764549.003.0075 ◽

2011 ◽

Author(s):

Douglass Taber

Keyword(s):

Transition Metal ◽

Quinone Methide ◽

State University ◽

Enantiomerically Pure ◽

Quaternary Centers ◽

University Of Oxford ◽

National University ◽

Cu Catalyst ◽

Both 1 and 3 are inexpensive prochiral starting materials. Tae-Jong Kim of Kyungpook National University devised (Organomet. 2008, 27, 1026) a chiral Cu catalyst that efficiently converted 1 (other ring sizes worked as well) to the enantiomerically pure ester 2. Alexandre Alexakis of the University of Geneva found (Adv. Synth. Cat. 2008, 350, 1090) a chiral Cu catalyst that mediated the enantioselective coupling of 3 with Grignard reagents such as 4 . The π-allyl Pd complex derived from 6 is also prochiral. Barry M. Trost of Stanford University showed (Angew. Chem. Int. Ed. 2008, 47, 3759) that with appropriate ligand substitution, coupling with the phthalimide 7 proceeded to give 8, readily convertible to (-)-oseltamivir (Tamiflu) 9, in high ee. Jonathan W. Burton of the University of Oxford found (Chem Commun. 2008, 2559) that Mn(OAc)3 -mediated cyclization of 10 delivered the lactone 12 with high diastereocontrol. John Montgomery of the University of Michigan observed (Organic Lett. 2008, 10, 811) that the Ni-catalyzed cyclization of 12 also proceeded with high diastereocontrol. Ken Tanaka of the Tokyo University of Agriculture and Technology combined (Angew. Chem. Int. Ed. 2008, 47, 1312) Rh-catalyzed ene-yne cyclization of 14 with catalytic ortho C-H functionalization, leading to 16 in high ee. Eric N. Jacobsen of Harvard University designed (Angew. Chem. Int. Ed. 2008, 47, 1469) a chiral Cr catalyst for the intramolecular carbonyl ene reaction, that converted 17 to 18 in high ee. Using a stoichiometric prochiral Cr carbene complex 20 and the enantiomerically-pure secondary propargylic ether 19, Willam D. Wulff of Michigan State University prepared (J. Am. Chem. Soc. 2008, 130, 2898) a facially-selective Cr-complexed o -quinone methide intermediate, that cyclized to 21 with high ee. A variety of methods have been put forward for the transition metal-mediated construction of polycarbocyclic systems. One of the more powerful is the enantioselective Rh-catalyzed stitching of the simple substrate 22 into the tricycle 23 devised (J. Am. Chem. Soc. 2008, 130, 3451) by Takanori Shibata of Waseda University. Inter alia, ozonolysis of 23 delivered the cyclopentane 24 containing two all-carbon quaternary centers.

Substituted Benzenes: The Subba Reddy Synthesis of 7-Desmethoxyfusarentin

Organic Synthesis ◽

10.1093/oso/9780190200794.003.0064 ◽

2015 ◽

Author(s):

Douglass F. Taber

Keyword(s):

Ethyl Cyanoacetate ◽

Strong Acid ◽

State University ◽

Max Planck ◽

University Of Texas ◽

Ru Catalyst ◽

Aryl Ketones ◽

Peking University ◽

University Of Bristol ◽

Andrey P. A ntonchick of the Max-Planck-Institut Dortmund devised (Org. Lett. 2012, 14, 5518) a protocol for the direct amination of an arene 1 to give the amide 3. Douglass A. Klumpp of Northern University showed (Tetrahedron Lett. 2012, 53, 4779) that under strong acid conditions, an arene 4 could be carboxylated to give the amide 6. Eiji Tayama of Niigata University coupled (Tetrahedron Lett. 2012, 53, 5159) an arene 7 with the α-diazo ester 8 to give 9. Guy C. Lloyd-Jones and Christopher A. Russell of the University of Bristol activated (Science 2012, 337, 1644) the aryl silane 11 to give an intermediate that coupled with the arene 10 to give 12. Ram A. Vishwakarma and Sandip P. Bharate of the Indian Institute of Integrative Medicine effected (Tetrahedron Lett. 2012, 53, 5958) ipso nitration of an areneboronic acid 13 to give 14. Stephen L. Buchwald of MIT coupled (J. Am. Chem. Soc. 2012, 134, 11132) sodium isocyanate with the aryl chloride 15 (aryl triflates also worked well) to give the isocyanate 16, which could be coupled with phenol to give the carbamate or carried onto the unsymmetrical urea. Zhengwu Shen of the Shanghai University of Traditional Chinese Medicine used (Org. Lett. 2012, 14, 3644) ethyl cyanoacetate 18 as the donor for the conversion of the aryl bromide 17 to the nitrile 19. Kuo Chu Hwang of the National Tsig Hua University showed (Adv. Synth. Catal. 2012, 354, 3421) that under the stimulation of blue LED light the Castro-Stephens coupling of 20 with 21 proceeded efficiently at room temperature. Lutz Ackermann of the Georg-August-Universität Göttingen employed (Org. Lett. 2012, 14, 4210) a Ru catalyst to oxidize the amide 23 to the phenol 24. Both Professor Ackermann (Org. Lett. 2012, 14, 6206) and Guangbin Dong of the University of Texas (Angew. Chem. Int. Ed. 2012, 51, 13075) described related work on the ortho hydroxylation of aryl ketones. George A. Kraus of Iowa State University rearranged (Tetrahedron Lett. 2012, 53, 7072) the aryl benzyl ether 25 to the phenol 26. The synthetic utility of the triazene 27 was demonstrated (Angew. Chem. Int. Ed. 2012, 51, 7242) by Yong Huang of the Shenzen Graduate School of Peking University.

C–H Functionalization

Organic Synthesis ◽

10.1093/oso/9780190200794.003.0019 ◽

2015 ◽

Author(s):

Douglass F. Taber

Keyword(s):

Oxidative Cyclization ◽

South Florida ◽

Hypervalent Iodine ◽

Direct Oxidation ◽

University Of Texas ◽

Ru Catalyst ◽

University Of Technology ◽

National University ◽

Indian Institute Of Science ◽

Masayuki Inoue of the University of Tokyo oxidized (Tetrahedron Lett. 2011, 52, 4654) the alkyl benzene 1 to the nitrate 2, which could be carried on to the amide 5, the nitrile 6, the alcohol 7, or the azide 8. X. Peter Zhang of the University of South Florida developed (Chem. Sci. 2012, 2, 2361) a Co catalyst for the cyclization of 7 to 8. Justin Du Bois of Stanford University reported (J. Am. Chem. Soc. 2011, 133, 17207) the oxidative cyclization of the sulfamate corresponding to 7 using a Ru catalyst. Seongmin Lee of the University of Texas showed (Org. Lett. 2011, 13, 4766) that the oxidative cyclization of 9 gave the amine 10 with high diastereoselectivity. Fabrizio Fabris of the Università di Venezia used (Tetrahedron Lett. 2011, 52, 4478) a Ru catalyst to oxidize 11 to the ketone 12. Ying-Yeung Yeung of the National University of Singapore found (Org. Lett. 2011, 13, 4308) that hypervalent iodine was sufficient to oxidize 13 to the ketone 14. Huanfeng Jiang of the South China University of Technology methoxycarbonylated (Chem. Commun. 2011, 47, 12224) 15 under Pd catalysis to give 16. Professor Inoue found (Org. Lett. 2011, 13, 5928) that the oxidative cyanation of 17 proceeded with high diastereoselectivity to give 18. Mamoru Tobisu and Naoto Chatani of Osaka University activated (J. Am. Chem. Soc. 2011, 133, 12984) 19 with a Pd catalyst to enable coupling with 20 to give 21. Rh-mediated intramolecular insertion is well known to proceed efficiently into secondary and tertiary C–H bonds. A. Srikrishna of the Indian Institute of Science, Bangalore found (Synlett 2011, 2343) that insertion into the methyl C–H of 22 also worked smoothly to deliver 23. The macrocyclic oligopeptide valinomycin 24 has nine isopropyl groups. It is remarkable, as observed (Org. Lett. 2011, 13, 5096) by Cosimo Annese of the Università di Bari and Paul G. Williard of Brown University, that direct oxidation of 24 with methyl(trifluoromethyl) dioxirane in acetone specifically hydroxylated at 8 (45.5%, our numbering), 7 (28.5%), and 6 (26%).

Best Synthetic Methods: Oxidation

Organic Synthesis ◽

10.1093/oso/9780199965724.003.0009 ◽

2013 ◽

Author(s):

Douglass F. Taber

Keyword(s):

Synthetic Methods ◽

Secondary Amines ◽

State University ◽

Air Oxidation ◽

Primary Alcohols ◽

Ru Catalyst ◽

Oxidation Of Alcohols ◽

Aldehydes And Ketones ◽

Diethyl Azodicarboxylate ◽

Karl A. Scheidt of Northwestern University described (Organic Lett. 2009, 11, 1651) the oxidation of primary alcohols such as 1 in the presence of an indole 2. The product 3, an active acylating agent, is readily converted to other esters and amides. K. Rajender Reddy of the Indian Institute of Chemical Technology, Hyderabad, developed (Tetrahedron Lett. 2009, 50, 2050) a protocol for the direct oxidation of a primary amine 4 to the corresponding nitrile 5. In the presence of ammonia, the same procedure converted aldehydes and primary alcohols into the nitriles. Several catalytic methods for the oxidation of alcohols to aldehydes and ketones have recently been put forward. René Grée of the Université de Rennes 1 found ( Tetrahedron Lett. 2009, 50, 1493) that ZnBr2 catalyzed the oxidation of alcohols with diethyl azodicarboxylate. Tsutomu Katsuki of Kyushu University designed (Tetrahedron Lett. 2009, 50, 3432) a Ru catalyst for the air oxidation of primary alcohols to aldehydes. Kazuaki Ishihara of Nagoya University showed (J. Am. Chem. Soc. 2009, 131, 251) that 1 mol % of 10 was sufficient to catalyze the oxidation of 6 to 7. With excess oxidant, 7 was carried on cleanly to 11. Nitroxyl radicals such as TEMPO have long been used to catalyze oxidations. Yoshiharu Iwabuchi of Tohoku University developed (J. Org. Chem. 2009, 74, 4619) a simple preparation of 13 , the most efficient such catalyst reported so far. This catalyst should also be useful for the oxidation reported by Professor Iwabuchi (Chem. Commun. 2009, 1739) of primary alcohols and aldehydes to the corresponding carboxylic acids. David S. Forbes of the University of South Alabama prepared (Tetrahedron Lett. 2009, 50, 1855) 16 by combining thioanisole with N-bromosuccinimide. The reagent 16 efficiently sulfenylated active methylene compounds. Jiri Srogl of the Academy of Sciences of the Czech Republic established (Organic Lett. 2009, 11, 843) conditions for the oxidation of primary and secondary amines to aldehydes and ketones. Olga A. Ivanova of Moscow State University demonstrated (Tetrahedron Lett. 2009, 50, 2793) that DMDO 21 could oxidize a sensitive amino cyclopropane such as 20 to the corresponding nitro compound.