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Baran Group Meeting Kyle W. Knouse JOC Year in Review : 1995 10/14/16

Statistics: Volume 60 1536 papers 8430 pages

Top 5 Most Cited Papers:

Palladium(0)-Catalyzed Cross-Coupling Reaction of Alkoxydiboron with Haloarenes: Publication Record: A Direct Procedure for Arylboronic Esters Katritzky, A. R. (20) Ishiyama, Tatsuo; Murata, Miki; Miyaura, Norio J. Org. Chem. 1995, 58, 904–912 Paquette, L. A. (15) 902 citations Denmark/Padwa/Marshall/Wong (8) Meyers, A. I. (7) "We need as heterocyclic chemists, to hold our heads Preparation and Characterization of Fulleroid and Methanofullerene Derivatives: Heathcock/Molander (6) high. Society cannot operate efficiently without us. All Hummelen, Jan C.; Knight, Brian W.; LePeq, F.; Wudl, Fred; Yao, Jie; Wilkins, Charles L. the impressive advances of biological chemistry, J. Org. Chem. 1995, 60, 532-538 genetic manipulation, enzymatic transformation, 793 citations Top Movies: antibody recognition, depend on the basic principles of Heterocyclic chemistry." Novel Alkaloids from the Sponge Batzella sp.: Inhibitors of HIV gp -Human CD Binding - Alan R. Katritzky 120 4 Patil A. D., et al. J. Org. Chem. 1995, 60, 1182-1188 534 citations Apollo 13 (19/20 publications involved reactions of benzotriazoles) Jumanji Conversion of Arylboronic Acids into Potassium Aryltrifluoroborates: Convenient Precursors of Arylboron Difluoride Lewis Acids Vedejs, E.; Chapman, R. W.; Fields, S. C.; Lin, S.; Schrimpf, . R. J. Org. Chem. 1995, 60, 3020-3027 Fun facts from 1995 342 citations world population: 5,674,380,000 -record for longest time in space is set, twice (366 days; 488 days) Phosphine-Catalyzed Cycloaddition of 2,3-Butadienoates or 2-Butynoates with -oklahoma city bombing Electron-Deficient Olefins. A Novel [3 + 2] Annulation Approach to Cyclopentenes -man says "Oklahoma was a good idea" then drives tank through Zhang, Chunming; Lu, Xiyan J. Org. Chem. 1995, 60, 2906-2908 Claremont neighborhood. 340 citations -internet becomes available to public (eBay founded, Windows 95 released) - DVD concept released

Top Songs: Gangsta's Paradise - Coolio Waterfalls - TLC This Is How We Do It - Montell Jordan Only Wanna Be with You - Hootie & the Blowfish Baran Group Meeting Kyle W. Knouse JOC Year in Review : 1995 10/14/16 Synthesis of Aromatic Heterocycles via Palladium-Catalyzed Annulation of Internal Asymmetric Ring Closure Reactions Mediated by a Chiral C2 Symmetrical Organoselenium Reagent Alkynes ArSe Richard C. Larock," Eul K. Yum, Mark J. Doty, and Kelvin K. C. Sham Robert Deziel* and Eric Malenfant JOC, 1995, 60, 3270-3271 JOC, 1995, 60, 4660-4662 R3 Pd: PdOAc O R Chloride: LiCl, n-Bu4NCl 2 3 R R Base: Na2CO3, NaOAc (77%) 12:1 facial R1 OH selectivity OEt SeX OEt R cat. Pd(0) Indoles R2 I base NR1 Me Me ArSe Ac NHAc N R OH 1,2-dihydro X = OTf R O Ph isoquinolines R=tBu only see exo product (95%) 29:1 facial I 80% selectivity CO2Et CO2H, NHBOC also acceptable nucleophiles OH O t-Bu Benzofurans I 65% Me Me Me Me Me OH O (2,4,6-Triisopropylphenyl)selenium Bromide (TIPPSe-Br). An in Situ-Generated Benzopyrans Reagent for Effecting Highly Selective Ring Closures of Homoallylic Alcohols to 52% I Ph Substituted Tetrahydrofurans Bruce H. Lipshutz* and Timothy Gross CO2Et Me SeAr O JOC, 1995, 60, 3572-3573 CO Me Me Me 2 O Me Me R Isocoumarins OH O I 72% R Me t-Bu Me Me Me SrAr Me SeX Me Me A New Version of the Peterson Olefination R Moncef Bellassoued and Nicolas Ozanne Me Me OH JOC, 1995, 60, 6582-6584 R Me O "a new simplified version of the Peterson olefination" X = Br Me SeAr Me O SiMe3 SeAr Me SiMe SiMe3 R Me R Me Bu SnH Me R 3 R-Li R Me 3 Li R OH O R Me R Me R R Me R R OH PhH, reflux O Me O Me Me SeAr O Me Me R R H R OH O SiMe3 R Solution to 5-endo trig R Me cyclization? R R cat. CsF, DMSO R OSiMe3 100°C

Avoids the use of strong organolithium reagents Baran Group Meeting Kyle W. Knouse JOC Year in Review : 1995 10/14/16

An Inexpensive Air-Stable Titanium-Based System for the Conversion of Esters to Total Synthesis of (-)-Thiangazole and Structurally Related Polyazoles Primary Alcohols Peter Wipf* and Srikanth Venkatraman Matthew T. Reding and Stephen L. Buchwald* JOC, 1995, 60, 7224-7229 JOC, 1995, 60, 7884-7890 O Me OH 1. DMP D-Thr-OMe, DCM O 2. Ph3P, I2, NEt3, THF Ses-HN PyBroP, DMAP H Non-Toxic OH Ses-HN OMe 3. MeNH2, MeOH Non-Pyrophoric N Me 60% i A 82% Me H Ti(OPr)4, Workup: BnO O O OBn Me PMHS Si Me NaOH or TBAF R1 O R1 OH - R OMe O Me 1. F Me2N O OBn Tolerant n 2. Coupling, A Me Functional Groups Me2N O N O 74% - O OBn NH-Ses 1. F HN Me O N 2. Coupling, A HO C Me 55% 1. F- 2 O Advantages: HN X OBn 2.Coupling, O -No need for organic solvent Bn MeOBn O X=Br,I -No need for anyhydrous/inert atm. Me 69% HN -inexpensive reagents, Ph Me2N O (byproduct of silicone production) Me O O N Me N O O Me 2 MeO 1. Pd(OH) , H N O PhSeO H, O 2 2 2 N 2. Burgess Me Me benzene, 70 °C O N Me N O 60% 60% Me Me N N A Mild, Regioselective Ketal Claisen Rearrangement Promoted by O Triisobutylaluminum AcSH ? N Scott D. Rychnovsky* and Jennifer L. Lee Me O 56% JOC, 1995, 60, 4318-4318 Me2N Ph O Me OMe i-Bu Al O N Me OH R OMe Me O 3 Me N O S Ph 2 MeSAc Me Me DCM N Me Me PPTS Me Me R N O 0 °C O SAc 1. NH3, MeOH Me S HN Me Me i-Bu Al 2. TiCl4, DCM N Me 3 3. PhSeO H, Me R O 2 Me Me O AlR HN benzene, 70 °C N 3 Me one-pot 89% Me Me OH SAc 60% S Me HN Ph OH O Ph Me OH Me Ph Me Ph ~ 5$ / gram NHSES Orthogonal to Tosyl and Boc HO Me Disadvantageous acid resulted in isomerization, Org. Synth. 1998, 75, 161 Yield Ratio lowering yield and product ratios No Change SESCl, Et N - 49% 75:25 3 NH F NH + Et N NH2 SiMe 2 3 58% 94:6 S 3 Isolate enol ether 69% 96:4 O O Daub, W. G.; JOC, 1983, 48, 3876 H+/ 120 °C 79% 9:91 Relative stability of Tosyl, but can be easily removed with F- Baran Group Meeting Kyle W. Knouse JOC Year in Review : 1995 10/14/16

A new, Titanium-Mediated Approach to Pyrroles: First Synthesis of Lukianol A Diastereoselective Cyclopropanation of Chiral Allylic Alcohols: A More Efficient and Lamellarin O Dimethyl Ether Reagent for the Relative Stereocontrol Alois Furstner,* Holger Weintritt, and Achim Hupperts Andre B. Charette" and Helene Lebel JOC, 1995, 60, 6637-6641 JOC, 1995, 60, 2966-2967 O OH OH OH OH R1 1 2 R1 NH O "low valent R1 R2 R R Ph R Ph R titanium" HN R2 syn:anti New R2 R2 Zn, CH I < 2:1 Sm(Hg), CH2I2 R2 2 2 Conditions Sm(Hg), CH2I2 1:5 to > 200:1 R = Me 7 : 1 1 : 6 R = Ph, t-Bu, 2-naphtyl, CO2Et Et 130 : 1 1 : 1 Bu 150 : 1 1 : 1.4 Method A: Premix TiCl4 and C8K to form (Ti-Graphite) All isolated yeilds > 75% for both new i-Pr > 200 : 1 > 200 : 1 Method B: Add TiCl3 and Zinc directly to subsrate and "old" conditions t-Bu > 200 : 1 > 200 : 1

1. ZnEt2, DCM -10 °C 1. H2O2, NaOH Ar Ar OBn OBn OBn 2. CH2I2, -10 °C O 2. BF3•OEt2, ether (reflux) Ar Ar H2, Pd/C O Ph R 3. NH2OH•HCl, pyridine (reflux) Ph R Ph R Ar Ar O 3. warm to rt 83% N E/Z (1:1) 1: 9 NH2 R = Me Et 1 : 2 Ar O i-Pr 19 : 1 Ar Ar Ar Ar O Ti - graphite, Improved Procedure for the Synthesis of Enantiomerically Enriched Ar Cl CO2Me DME, reflux Cyclopropylmethanol Derivatives O Andre B. Charette,* Sylvie Prescott, and Christian Brochu NH CO Me E/Z (2.5:1) 52% N 2 JOC, 1995, 60,1081-1083 NH2 73% H Scalable as long as -10 °C O CO2Me Me2NOC CONMe2 temperature is maintained Ph OH during addition MeO OMe Ph OH O O HO OH B 93% ee (> 98% yield) Me O (1.1 eq.) Bu O BnO OH Ar Ar Br 1. KO-tBu, H2O, ether Zn(CH2I)2•DME (3-5 eq.) K2CO3, acetone 2. Ac2O, NaOAc, reflux BnO OH DCM, -10 °C reflux MeO C 93% ee (> 98% yield) CO Me 2 N 3. BBr3, DCM O N 2 MeO2C N H 91% O 53% O lukianol A Diastereoselectivity in the Cyclopropanation of 3,3-Bimetallic 8 steps, 12% yield Allylic Alcohols. Preparation of Diastereomeric Cyclopropyl Carbinols via a Simple Oxidation-Reduction Sequence O Mark Lautens* and Patrick H. M. Delanghe R JOC, 1995, 60, 2474-2487 R TMS OMe HO TMS R Sm(Hg), CH I TMS 2 2 OH OH R3Sn R3Sn R3Sn OH 1 : 20 (80%) R R 1. TPAP, NMO, DCM TMS TMS OH OH 2. LAH, THF R3Sn R3Sn 1 : 20 (85%) Baran Group Meeting Kyle W. Knouse JOC Year in Review : 1995 10/14/16

Sodium Diethyldialkynylaluminate, A New Chemoselective Alkynylating Agent Selective, Electrophilic Fluorinations Using N-Fluoro-o-benzenedisulfonimide Jin Hee Ahn, Meyoung Ju Joung, and Nung Min Yoon* Franklin A. Davis,* Wei Han, and Christopher K. Murphy JOC, 1995, 60, 6173-6175 JOC, 1995, 60, 4730-4737 F3C SO2 N F CR "The reaction mixtures were exceptionally clean" Et H toluene Et F3C SO2 Al disulfonimide byproduct is highly H + RC CH Al + 2H2 O O Na CR water soluble -low boiling liquid Et rt Na Et S By contrast, fluorinations using NFSi require an -6 step synthesis SDDA SDAA N F O O alkaline wash to remove the dibenzenesulfonimide -liquid F2, CR3 S -special reactor Et Me O byproduct. Al O Me O CR3 3 OMe 3 NFOBS O Na Et R SO NHMe O F 1.1 eq. OH Me O O 2 F O Initial Report and Preparation: Me R1 R2 Tetrahedron Lett. 1991, 32, 1631 Ph toluene R1 R2 N 3 Me Me F O 0 °C or rt. F Me O O Aromatics OMe Most yields half. Silyl Enol Ethers CHO CHO Ph Ph Most Yields doubled O O F Me O en route to O Direct F EtO P CO Me chiral oxidants Br O Dicarbonyl Compounds EtO 2 O Me Most Yeilds Doubled N CO Me CN F S 2 O O

O2 1. PCl5, 110 °C. SO K 2. NH , EtOH S Highly Enantiocontrolled Strategy for the Synthesis of Benzylic Quaternary Carbon 3 3 3. Dowex NH 10% F2 in N2 Centers. A Formal Total Synthesis of (-)-Mesembrine S NFOBS Hideo Nemoto, Tetsuro Tanabe, and Keiichiro Fukumoto* (87%) SO3K O2 (>90%) JOC, 1995, 60, 6785-6790

(+)-DIPT, HO O t-BuOOH MeO OSiR MeO OH Ti(OiPr)4, MeO N 3 Asymmetric Synthesis of the Volatile Anesthetic 1,2,2,2-Tetrafluoroethyl O Me DCM, -40 °C Chlorofluoromethyl Ether Using a Stereospecific Decarboxylation of Unusual MeO TMS 65% (92% ee) MeO TMS Stereochemical Outcomet Leonid A. Rozov, Patrice W. Rafalko, Suzanne M. Evans, Linda Brockunier, and Keith Ramig* JOC, 1995, 60, 1319-1325 O CF3 O CF F Me Me 3 MeO OMe F C CF Resolve F CO H 3 O O 3 2 H F MeO OMe Me 99% ee KOH, TEG 99% ee CO2H Me F O CF3 F F Me DMPU, 200 °C O CF3 3 steps O 70-80% Me Formal Synthesis HO2C F F H 99% ee 97% ee O O N Acyclic decarboxylation with inversion H Me (-)-mesembrine Baran Group Meeting Kyle W. Knouse JOC Year in Review : 1995 10/14/16

Total Synthesis of (+)-Dactylol via a Novel [3 + 5] Annulation Approach Novel Total Synthesis of (+)-Eremantholide A Also see: JOC 1995, 60, 8179-8193 Gary A. Molander* and Paul R. Eastwood Ken-ichi Takao, Hiroshi Ochiai, Ken-ichi Yoshida, Takahiko Hashizuka, Hirokazu Koshimura, JOC, 1995, 60, 4559-4565 "It was unclear what Kin-ichi Tadano,* and Seiichiro Ogawa Me had become of the cis isomer" JOC, 1995, 60, 8179-8193 O Me O OTMS O O 7 steps, Me O O PivO O Me gram scale TiCl4, Ti(O-i-Pr)4 Me Me O O H O O O 7 steps O Me 4 steps Me O HO H DCM, -95 °C Me Me Me Me Me O Me Me Me 83% Me Me O Me OH (+) pulegone MeO EtO O O TMSO OMe Previous Synthesis: 6 : 1 TMSO OTBS OTBS J. Org. Chem. 1987, 52, 1201. O-LA O O-LA PivO OMe O NaIO , O Me Me O 1. PCC OCHO 4 TMSO OMe O PivO MeOH Me 2. Et3N, MeOH HO TrSbSl6 Me Me Me CHO HO 88% 3 steps DCM, -78 °C H H MeO MeO 77% Me Me Me NaH, CS2 then MeI both diol isomers result O O THF, -15 °C in same product CO Me OMe 2 Me OMe OMe 1. NaCl, DMSO, O 1. O , PPh O Me O 3 3 H2O, 140 °C, 84% PivO Bu3SnH, AIBN, 2. DBU O Me H+ 2. Tebbe, 0 °C, 92% RhCl3•3 H2O S Me O O Me Me Me O toluene (0.01M) H Me EtOH, H O 70 °C H R O Me H Me 2 S MeO reflux Me H 96% (12 : 1) Me PivO PivO 4 steps O 90% Rapid entry to carbocylic framework, remaining challenge is freeing O 8-membered ring via reductive ether cleavage Me PivO O Me Me Me Me Me Me O O O O Me H Me OMe 1. NaBH , MeOH Me O HO Me 4 : 1 Me NaHMDS, 4 Half the yield of H Me 15-C-5 O 2. Ac2O, pyridine O O OMe O O the model system Li, H N(CH ) NH 2 2 2 2 Me Me toluene, -78 °C 3. 3-step PG O Me O H H H H 15% OTf manipulation Me Me 40 °C O Me Me Me Me H O PivO PivO 10 : 1 (36%) + Me (25%) Me Me (+)-Dactylol, O O OHC O Me OH 7-steps from known advanced intermediate 1. KHMDS, THF H Me 2. MsCl, pyridine O O 2 steps OMe Me O Me 3. DBU H 4. HCl/THF O Me O O Me Me Me O (+)-Eremantholide A Baran Group Meeting Kyle W. Knouse JOC Year in Review : 1995 10/14/16

Me Me Me Isolated O O O O Me OH Natural OH H Products HO HO S N H3C(H2C)n O H O O O N H N S HO (CH ) CH O HO O 2 n 3 H O OH O H N H O OH O NH HN H H H Me Me n=4,6; secosyrin 1, 2 n=4,6; syrilbutin 1, 2 NH N 2 N OH pteroenone Me Me Me Me O O H Me H ritterazine B/C O Me N Me O O Me pseudodistomin C H O OH nostocyclamide Me Me N P P 3 O NMe3 Me O OCH2(CH2)20CH2O Me O O O O OH Irbacholine Cl Me Ketone = Cl OH H Hydrate = suberitone B oxopuupehenol Me Me Me H Me OH H OH OH Me N Me O Me OH O Me OH N N H Me Me O H O O N paxinorol Me OH H H Me Me OAc Me Me H O NH O Me Me O Me suberitenone A malokinenone chloropuupehenol NH Me Me NH HN Me Ph Me Me Me Me O Me H Me Me Me H O Me Me O OH O stylopeptide 1 H Me H oteromycin NH Me O OH H O Me Me Subglutinols A and B HO H O Me epitaondiol Me Me OH OH Me "The First Polycyclic Me HO HO Meroditerpenoid Containing Two O Me HO Fused Six-MemberedRings HO Forced into the Twist-Boat N Me N S O O O MeO Conformation" O Me Me O Not Included Isolations: S O O microcystin - heptapeptide O Me H Petriellin A - depsipeptide dolabellin OH OH Me Me Me Cl O Me O Cl O HO Me Me H caribenolide H Me H Baran Group Meeting Kyle W. Knouse JOC Year in Review : 1995 10/14/16 OH Me Me Selected Syntheses of Natural Products and Drugs HO Me Me Me OP O 3- Me O O NHMs 2 6 Me Me Me Me (+)-laurene - Me Me Me H Me Me Me OH Me O O O O O Myers, A. I. (6511) rac-mediterraneol B - O (–)-mevalonic acid - Me Me Davis, F. A. (6148) OH presqualene diphosphate - Kakiuchi, K. (3318) O Structure Revision O N Poulter, D. C. (941) rac-kallolide B - MK-0499 - OHCHN OMe OMe Marshall, J. A. (796) Mecrk, (4324) O OH O Me NC Me Me HO Me O O N O O NH OH Me O H B H H N MeO Me O H2N N OH DuP-714 - (–)-lipistatin - Me H OH O NH Du Pont Merck (3717) Kocienski, P. J. (7334) NH O Thrombin Inhibitor nitraramine - Koomen, G. J. Me juncosol - OMe Me N OMe Me Me Jacobi, P. A. (377) MeO (–)-O-methyl-ancistrocladine - H H N NHAc H Rizzacasa, M. A. (5702) Me Me O O OH O S (+)-codaphniphyllin - MeHN O O Heathcock, C. H. (1120) N N N HO H Me O O Me N N (+)-y-lycorane - O O (–)-Thiangazole - N CO2H O Me OH S H Me Mori, M. (2016) OH Me Wipf, P. (7224) (–)-mesembrine - O OH HO O OMe OMe O O N Ph OH Fukumoto, K. (6785) MeO OMe H S Lavendustin A - Me H O H HO O O Me ARIAD Pharm. (4287) Me H N CO2H (–)-deoxypodophyllotoxin - H Me Ph O Me Charlton, J. L. (588) Me O Me Me Me CO Me (+)-eremantholide A - (+)-neocryptotanshinone, - 2 FPL-64176 - Me Tadano, K. (8179) Danheiser, R. L (8341) H HN Dow Research Institute (4947) N N Me Me H ilimaquinone - Snapper, M. L. clavicipitic acid - OH O O Cl HO Murakami, Y. (1486) Me OH N O N N (+)-cyclophellitol - HN NH Me OH (+) and (–)-epibatidine Bergstrom, C. P. HO H Me O N N O Rapoport, H. (2683) (–)-rosmarinecine - OH Denmark, S. E. (3574) O indolizidine 207A, HO HO Me O O N Taber, D. F. (529) OH HO OH HO Me OH Me Me Me Me R Me O H O O OH HO N O P H HO O OH OH OMe OH O O (+)-galactostatin - (–)-cephalotaxine - magnolol, (–)-monoterpenylmagnolol - Dondoni, A. (4749) "Dinucleotide Spore Photoproduct" - (–)-ebelactone A (R=Me) and B (R=Et) - LeBel, N. A. (1856) Mori, M. (115) Begley, T. P. (6256) Paterson, I. (3288)