joc year in review: 1989 baran group meeting justine …
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SelectedIsolations
NH
Me
OH
Me
MeMe
NH
Me
OH
Me
MeMe
tubingensen A (4743) nominine (2530)
NO
O
N
Me
O
O
Me
HO2C
H
H
H
HH
H
H
HOMe
gelsamydine (3199)
Me
isocyanoneopupkeanane (2095)
MeMe
CNMe
MeO
O
O
MeOOMe
NH
R
R=H, limalongineR=Cl, chlolimalongine (3491)
O
MeO Me
O
HO
Me
R
R=α-Me, R1=H, crotoxide A
R=CH2, R1=α,β-OH, crotoxide B (1654)
R1
O O
CO2MeO
Me H
H
(±)-sarracenin
NH
N H
O
H
(±)-meloscine (α-H)(±)-epimeloscine (β-H)
O
H
Me
OH
OH
OAc
Me
Me
HOO
forskonlin
N
N NMe
MeOMe
(±)-alchorneine
N
NN
O
Me
O
amphimedine
Me
CO2H
Me
MeMe
H
HMe
retigeranic acid
SynthesesDiscussed
SomeSynthesesNotCovered• Danishefsky,13-oxygenatedprostanoids.6016-6018.• Nicholaou,geomertric isomersoflipoxin-A4andlipoxin-B4.5527-5535.•Meyers,unnatural(+)-aspidopermine.4673-4676.• Paquette,trixikingolide.3334-3337.• Boger,K-13.2498-2502.
Publication Record Paquette, L.A. 14Padwa, A. 9Brown, H.C. 9Fraserreid, B. 8Faulkner, D.J. 8Rapoport, H. 7 Olah, G.A. 7Marchand, A.P. 7Clardy, J. 7Barrett, A.G.M. 7Schreiber, S.L. 6Lenoble, W. J. 6
Top 5 Most Cited1. "Investigation of the Synthesis of Ortho-Substituted Tetraphenyl- porphyrins." Lindsey, J.S.; Wagner, R.W. 54(4), 828-836.
2. "Atom Transfer Cyclization Reactions of Alpha-Iodo Esters, Ketones, and Malonates - Examples of Selective 5-exo, 6-endo, 6-exo, and 7- endo Ring Closures." Curran, D.P.; Chang, C.T. 54(13), 3140-3157.
3. "Host Guest Complexation .48. Octol Building-Blocks for Cavitands and Carcerands." Tunstad, L.M.; Tucker, J.A.; Dalcanale, E.; et al. 54(6), 1305-1312.
4. "Absolute Electronegativity and Hardness - Applications to Organic- Chemistry." Pearson, R.G. 54(6), 1423-1430.
5. "Substituted 1,4-Dihydropyrimidines .3. Synthesis of Selectively Functionalized 2-Hetero-1,4-Dihydropyrimidines." Atwal, K.S.; Rovnyak, G.C.; OReilly, B.C.; et al. 54(25), 5898-5907.
Noble Prize- Chemistry Altman, S. and Cech, T.R. "for their discovery of catalytic properties of RNA"Wolf Prize- Chemistry Battersby, A.R. and Arigoni, D. "for their fundamental contributions to the elucidation of the mechanism of enzymic reactions and of the biosynthesis of natural products, in particular the pigments of life"Priestley Medal Pimentel, G.C.
General StatsVolume: 54Issues: 1-26Pages 1-6140Total Articles: 1,372
Notable Events- Jan. 20: George H.W. Bush inaugurated - Mar. 24: Exxon Valdez tanker rupture in AK- June 4: Tiananmen Square Massacre- Nov. 11: Berlin Wall opens to the West
See also: K. Foo 2011 GM, "JACS Year in Review: 1989"
Justine deGruyterBaran Group Meeting
05/23/2015JOC Year in Review: 1989
AnodicOxidationofStudiesofp-Methoxyanilides.AGeneralMethodforPreparationofAcylated Quinone Imine Ketals.Swenton,J.S.;Bonke,B.R.;Chen,C.-P.;Chou,C.-T.51-58.
O
O
N2
Rh2(OAc)4
O
CHO
O
O
N2Rh2(OAc)4
O H
O
O
CHO
H+
OH
CHO
S O
N2
S S
O
H+[Rh]
O
CH2CH2COCHN2[Rh]
O
O
O
O
O
HO
HO
H+
Intramolecular Cyclopropanation ReactionofFuranyl Diazo Ketones.Padwa,A.;Wisnieff,T.J.;Walsh,E.J.299-308.
N
R
EWG
NMe
OON
NMePhOC
O
O
H
HH
CH2CHEWG
NMe
O
O
N
NMe
O
O
EWG
PhOC
N
NMe
O
O
HN
O
O
H
H
H
H
HHH
H
H
PhOC
AShort,Oxetane-BasedSynthesisof(±)-Sarracenin.Hoye,T.R.andRichardson,W.S.688-693.
Electron-DeficientIsoxazoles:1,3-DipolarCycloadditions ofEthyl4-nitro-3-phenylisoxazole-5-carboxylatewithDiazoalkanes.Nesi,R.;Giomi,D.;Papaleo,S.;Bracci,S.706-708.
NO
E
NO2Ph
N
O
N
N
Ph NO2
ER
R
N
O
R R
NO2
E
N
O
N
Ph NO2
E
N
H
N
O
Ph
N
N
E
N
O
Ph
N
N
E
N
N
N
O
Ph
N
N
E
N
N
R2C=N2
R=H, Me
-N2R=H
-HNO2
xs
H2C=N2
H2C=N2
-N2
H Me
Ohυ
OMeH
Me HOH
CR2
CO2Me
OHC
Me HOH
CR2
CO2MeOHC
OHMe
HOOH
Me
H HO MeH
CR2
CO2Me
O O
CO2MeO
Me H
H
OHC E
" "
O3
H+
1. remove " "
2. O3
"-OH" 1. activate "-OH"
2.OHC E
" "
(±)-sarracenin
Tandem1,3-DipolarCycloadditions ofPyridinium orIsoquinoliniumMethylides withOlefinic Dipolarophiles LeadingtoCycl[3.2.2]azines.EnamineRouteasaNewGenerationMethodofAzomethine Ylides.Kanemasa,S.;Takenaka,S.;Watanabe,H.;Tsuge,O.420-424.
HN R 1
O
R2
OMe
R 3
N
O
R 1
R2
R 3
MeO OMe
-2 e-
LiClO4, MeOH,
NaHCO3 or
2,6-lutidine
HN
O
R
OMe
HN
O
R
MeO OMe
R=H, OMe ?
An anomaly.
Justine deGruyterBaran Group Meeting
05/23/2015JOC Year in Review: 1989
MediatedElectrochemicalSynthesisofAromaticAldehydes,Ketones,andQuinonesUsingCeric Methanesulfonate.Kreh,R.P.;Spotnitz,R.M.;Lundquist,J.T.1526-1531.
Me
Me
Me
Me Me
CHO
Me
Me
O
O
PhMe PhCHO
PhEt PhCOMe
1,1-Bis(methylthio)-2-(phenylsulfonyl)ethene:AUsefulKeteneAnionEquivalent.Yamamoto,M.;Takemori,T.;Iwasa,S.;Kohmoto,S.;Yamada,K.1757-1760.
• O
PhO2S
"doubly umpolunged enolate equivalent"
SMe
SMe
PhO2S
SMe
SMeE
PhO2S
E+= MeI, BnBr, BzCl, BnCHO, acrolein, MVK, TMSCl, CH3CHCH2O, PhNCO
SMe
SMe
PhO2S
Me
O
Me
OH
CO2Et
SO2PhO
SO2Ph
O
Me
in EtOH:in tBuOH:
56%0%
28%96%
SMe
SMe
PhO2S
R
HO pTsOH
O O
SO2Ph
R O OR
Al(Hg)
R= MeR= Ph
86%98%
33%68%
1. NaBH4
2. pTsOH in ROH
nBuLi
E+
Me3SiN3 2 F3CSO3H NH2N2+OSO2CF3
- Me3SiOSO2CF3
NH2N2+OSO2CF3
-
R NH2
H
- F3CSO3-
RNH2
R
+ + substratebenzenetolueneo-xylenemesitylenePhClPhBr
yield (%)959693959373
o: m: p
54: 9: 37
45: 7: 4852: 6: 42
Trimethylsilyl Azide/Triflic Acid,aHighlyEfficientElectrophilic Aminating Reagent.Olah,G.A.;Ernst,T.D.1203-1204.
Me3SiOOSiMe3
R OSiMe3
H
ROH
R CF3SO3H
- H+
then CF3SO3H
substratebenzenetoluenemesityleneo-xylene
naphthalene
PhCl
yield (%)77889463
92
76
o: m: p
63: 10: 27
(2,3-)48: (2,6-)22: (3,4-)30(α-) 67: -- : (β-) 3363: -- : 37
DABCO 30% H2O2 DABCO•H2O2 (Me3SiO)2+THF
0°C
TMSClCH2Cl2
0°C
Oxyfunctionalization ofHydrocarbons.14.Electrophilic HydroxylationofAromaticswithBis(trimethylsilyl)Peroxide/Triflic Acid.Olah,G.A.;Ernst,T.D.1204-1206.
NO
Ph
H
Ph
H2C C CHSO2Ph
NH
O
SO2Ph
Ph
H+NH
SO2Ph
N
PhPh
O
PhO2S
rt
SynthesisoftheBenzazepin-4-oneRingSystemviaDipolarCycloaddition ofN-Phenylnitrones withActivatedAllenes.Padwa,A.;Kline,D.N.;Norman,B.H.810-817.
TotalSynthesisof(±)-Meloscine and(±)-Epimeloscine.Overman,L.E.;Robertson,G.M.;Robichaud,A.J.1236-1238.
O
O
O
O
Me
13 steps NMeO2C
H
OBnO
NC OTMS
NHBoc
N
O
O
H
OBnO
BocHN
HNH
OBn
HO
BocHN
N
X
O
HBocHN
NH
OBn
MeO2C
BocHN
NH
N H
O
H
X
(±)-meloscine (α-H)(±)-epimeloscine (β-H)
1. THF, −70°C 3 M HCl quench
2. LiOH, MeOH
1. Ph3P=CH2, rt2. KOH, EtOH 130°C
paraformaldehyde
CSA, PhH, reflux
X=H
X=N2
hν xs KOH
EtOH/H2O0°C to 150°C
Et2O/MeOH
Justine deGruyterBaran Group Meeting
05/23/2015JOC Year in Review: 1989
OH
NH2NH2
X
NHRNHR NHR
NR
NHR
NHR
Nu
OH
NHZNHZ
OSO2Me
NHZNHZNHZ
NHZ
CN
NHZ
NHZ
Cl
NHZ
NZ
NHZ
NHZ
OR
R=OCCH3
R=H
General Scheme.
KCN, 18-c-6
NaH/DMF
1. KOtBu/THF2. CH3CO2H, reflux
1. NaH/DMF2. 5% HCl
5% HCl CH3CO2H
MeCN
K2CO3
MeOH:H2O
Selected Examples.
NHTs
NHTs
OTs
NHTs
NTs
NHTs
NHTs
Me
N
Ts
O
CO2Et
TsHN
NHTs
NHTs
CO2H
NaOMe
MeOH
MeMgBr, THFCH2(CO2Et)2
NaOEt, EtOH
6 N HCl
AConvenientSynthesisofVicinalDiamines.Jones,D.A.;Arinivasan,A.;Kasina,S.;Fritzberg,A.R.;Wilkening,D.W.1940-1943.
TheFIrst ExampleofaCatalyticWittig-TypeReaction.Tri-n-butylarsine-CatalyzedOlefination inthePresenceofTriphenyl Phosphite.Shi,L.;Wang,W.;Wang,Y.;Huang,Y.-Z.2026-2028.
SynthesisofOxidizedSpiroketals via2-FurylKetone Oxidation-Rearrangment.Perron,F.;Albizati,K.F.2044-2047.
RCHO + BrCH2X + (PhO3)P
n-Bu3As (cat.), K2CO3 (s)
THF-MeCN, rtR
X + (OPh3)P
R=p-ClPhPhH2-furyl2-thiophenyl2-pyridylPhCH=CH
X= CO2CH3, C(O)Ph
Yield (%)878680756861
n-Bu3As
n-Bu3As+CH2XBr-
n-Bu3As+C-HX
n-Bu3AsO
BrCH2X
K2CO3
RCHO
RCH=CHX
(PhO)3P
(PhO)3PO
OR
OR Li O
R OH
OO
O
O
R
HO
O
OTBS
O
OTBS
O
O
O O
Me
OH
O
O
O
Me
OHOH
nBuLi
THF, −78°C
O
O
−78°C
2.0 equivNBS
aq. THF0°C to rt
+
Mechanistic Pathways for N-dealkylations of Amines by Cytrochrome P-450.
R N
O
R1
R2
R= PhCH2CH2,
Ph, p-O2NC6H4,
C6F5, H
R1= CH3, CD3
R2= CH3, CD3,
H, CHO, CH2OCH3,
CH2OH
R N
O
R1(R2)1
H
Substrate Scope.
ElectrochemicalModelforCytochrome P-450.N-Demethylation ofTertiaryAmidesbyAnodicOxidation.Hall,L.R.;Iwamoto,R.T.;Hanzlik,R.P.2446-2451.
Electroorganic Chemistry.116.ElectrochemicalTransformationofAldoximes toNitriles UsingHalogenIonsasMediators.IntermediaryFormationofNitrile Oxides.Shono,T.;Matsumura,Y.;Tsubata,K.;Kamade,T.;Kishi,K.2249-2251.General Scheme.
N
R
OHelectricity
electrolyteMeOH
RCN
Mechanism.
Me
Me
Me
N OH
Me
Me
Me
N O
Me
Me
Me
CN
MeN
OH
5
-2e-, NaI
styrene
MeOHN
O
Me(H2C)5
Ph
N
OH -2e-, NaI
styrene
MeOHN
O
Ph
Ph
Ph
Selected Examples.
Justine deGruyterBaran Group Meeting
05/23/2015JOC Year in Review: 1989
AFormalSynthesisofForskolin:AnElectrocyclization Approach.Venkataranman,H.;Cha,J.K.2505-2506.
Cyclohexadienone AnnulationsofArylCarbene ComplexesofChromium:NewStrategiesfortheSynthesisofIndole Alkaloids.Bauta,W.E.;Wulff,W.D.;Pavkovic,S.F.;Zaluzec,E.J.3249-3252.
X
R1
(OC)5Cr
OMe
X
OMe
Rs
RLR2
R1
R3R 2
R3
X
R2
R3
OR1
OMe
Rs
RL
NMe
OMOM
OMe
Cr(CO)5
NH
O Ph
benzene, 50°C
NMe
O
HN
PhO
OMe
MOMO
N
N
R1
Me
R 3
R 2
H
R4
Me
vindoline: R1= OMe, R2= OAc
R3= OH, R4= CO2Me
RLC CRs
R1≠ H
?
RLC CRs
R1≠ H
?
InterruptedPolymerizationofAcrylates:SequentialMichael-Michael-DieckmannCyclizations forEasy,One-pot,2+2+2ConstructionofPolyfunctionalizedCyclohexanones.Posner,G.H.;Shulman-Roskes,E.M.3514-3515.
SynthesisofTwoUseful,Enantiomerically PureDerivativesof(S)-4-Hydroxy-2-cyclohexenone.Audia,J.E.;Boisvert,L.;Patten,A.D.;Villalobos,A.;Danishefsky,S.J.3738-3740.
OO
OHHO
HO
MeMe
O
HO
OO
MeMe
O
OO
MeMe
O
OO
MeMe
O
OTBS
O
OH
O
OPMB
OR'
R
OR'H
NaIO4MsCl, TEA
CH2Cl2
H2, Pd(OH)2/C
DBU, TBSClPhH, heat
DBU, PhH or K2CO3, aq. THF
PMBOC(NH)CCl3
DCM
BF3•OEt
Me2CuLi
TMSCl
OTBS
OEt
HgI2
RO
O
R1
R
2
1. LDA
2. 2
3. H+
CO2R
OR
O
RO
O
O
R1
R2
R R1 R2 % Yield
Et
Et
Et
Me
H
H
H
H
H
CH3
Ph
SPh
49
70
66
72
Et
Me
Et
R R1 R2 % Yield
NMe
58
64
45
Functionalization ofOlefinsbyAlkoximidoylnitrenes.Subbaraj,A.;Rao,O.S.;Lwowski,W.3945-3952.
EtOCNSO2CH3
N
ArOCNSO2CH3
N
MeOCNCN
N
EtOCNCN
N
R
+ NG
N
R
G
heat
NHGRCH
R
2
R1CH
R
2
R1
R
2
R1
N
R
H
CH
R
2
R1
H2O
O
H
Me
OH
OH
OAc
Me
Me
HOO
Me
OH
Me Me
O
Me
OCH2OBn
Me Me
MeMe
CO2EtOH
Me Me
MeMe
CO2Et
O
Me Me
MeMe
R 3
R4
O
Me
Me
OMe
O
Me
MeMe
HMe
OH
Me
OH
O
Me
Me
OMe
Me
OH
O
O
O
Me
MeMe
HMe
O
O
4 steps W-2 Raney Ni
EtOH, rt
1. PCC, CH2Cl22. NaBH4, EtOH
1. LAH, Et2O, 0°C
2. tBuOOH, VO(acac)2
PhH
PCC
CH2Cl2
PCC
CH2Cl2
Na, anthraceneTHF
4 steps
forskonlin
R4= R5= O
R= H, R5= OH
Justine deGruyterBaran Group Meeting
05/23/2015JOC Year in Review: 1989
Functionalization ofPhenylRingsbyImidoylnitrenes.Dabbagh,H.A.;Lwowski,W.3952-3957.
Synthesesof(±)-Alchorneine and(±)-Isoalchorneine.Buchi,G.;Rodriguez,A.D.;Yakyshijin,K.4494-4496.
O O
H
O O
M
O O
R R
OBuLi
(+MXn)
R+ Amberlyst-15O
OH
pentricin
O O
RBu
O1. BuLi
2. BuIBu
O O
RLi
O OtBu
O
R
O
OMe Me
OH
2. Amberlyst-15 aq. THF
3. H+
1.
ApplicationsofMetalated Cyclopropenone Ketals inaGeneralSynthesisofCyclopropenones.AnEfficientSynthesisoftheAntibioticPenitricin.Isaka,M.;Matsuzawa,S.;Yamago,S.;Ejiri,S.;Miyachi,Y.;Nakamura,E.4727-4729.
Stereocontrolled ConstructionofHydroazylenones bySequentialAnionicOxy-CopeRearrangement-SN'-Allylic EtherDisplacement.Paquette,L.A.;Shi,Y.-J.5205-5207.
O
OR
R1
R4
R2
R 3
R
R1 O[Ru]
R2
R 3R4 O
O
O
R
R1 OH
R2
R 3O
R
R1 OH
R2
R 3R4 OH
R1
O
R
O
R4
R2
R 3
Ru(II) -Ru(II)
R=CH2
R1-R4=H
-Ru(II)
-Ru(II)
2R1-H-Ru(II), -•R4
R1-H
R= (CH2)n
R1-R4= H, alkyl, alkenyl
O
O
R
H
H
R
OR
H
H
R
[Ru]
O
HO
R
O
O RR
Ruthenium(II)-CatalyzedReactionsof1,4-Epiperoxides.Suzuki,M.;Ohtake,H.;Kameya,Y.;Hamanaka,N.;Noyori,R.5292-5302.
EtOCNCN
N
N
NCN
OEt
HN
OEt
NCN
EtOCNSO2CF3
N HN
OEt
NSO2CF3
R
R
R
R
R
R
NHG
NHG
NHG
R'OCNSO2CF3
N
R R R
R
R'OCNSO2CF3
NR RR
NHG NHG
NHG
RR
NH2N
MeS
O
CH2
Na N
N
Me
Me Br
Me
BrBzO
Me
Me
N
CN
Me
OBz
Me
Me
N
Me
OBz
NHOCH3HN
NH2OMe•HCl
PdCl2(CH3CN)2
CH2Cl2, 40°C
Pd(PPh3)4 (cat.)
Et3N, MeCN, 50°C
N
N
HN
OMe
Me
Me
N
N NMe
MeOMe
(±)-alchorneine
O
MeO
H
H
Me
Me
H
H
Me
Me
MeO
H
OH
O
H
Me
Me
HOMe
O
H
A B
+
MeMe
OMeH
O
Me
MeH
H
H
H
H O MeMe
OMe
H
H+ H+
KH, 18-c-6
THF, Δ
O
HH
HMe
Me
OMeH
A
via:
H
O
OMeR
O
OMeR
O
H
H
R
Justine deGruyterBaran Group Meeting
05/23/2015JOC Year in Review: 1989
AnExpeditiousRoutetotheNorthernPartofRetigeranic AcidAfrom(R)-Carvone.Llera,J.M.;Fraser-Reid,B.5544-5548.
AnApproachtoAmphimedine andRelatedMarineAlkaloidsUtilizinganIntramolecular Kondrat'eva PyridineSynthesis.Subramanyam,C.;Noguchi,M.;Weinreb,S.M.5580-5585.
NHOCH3
Br
CHO
Br Br
Br
NAcNAc
NAc
(n=1) NH2OCH3-HClBH3-py.
(n=3) Ph3P=CHCO2CH3;Mg, MeOH, DIBAL;NH2OMe-HCl, BH3-py.
BrMgCH2CH=CH2,BH3-THF; H2O2, NaOH;
oxallyl chloride, NH2OMe-HCl;BH3-py.
CH3Li; tBuLi; RCOCl
n
DisplacementsattheNitrogenofLithioalkoxylamides byOrganometallic Reagents.Beak,P.;Selling,G.W.5574-5580.
N
OMe
OR
O
MeO
NH2
1. pTsOH, PhMe,
90°C
2. NaCNBH3, MeOH,
AcOH
N
OMe
NH
MeO2CN
OMe
NH
MeSe O
Me2AlSeMe
PhMe
N
OMe
NH
O
N CO2Me
CNCH2CO2Me
Et3N, Cu2O, THF
N
OMe
N
O
N
HO
1. Ca(BH4)2
THF/MeOH
2. Ac2O, HCO2H
THF, rt
R
R=HR=CHO
N
N
N
OMe
OH
CHO
o-DCB, DBN
150°C
N
N
N
OMe
OH
CHO N
NN
O
Me
O
amphimedine
MnO2, CHCl3rt
StudiesontheSynthesisofIndolo[2,3-a]quinolizidineSystem.Rubiralta,M.;Diez,A.;Bosch,J.5591-5597.
Me
O
Me
O
CO2Me Me
O
CO2Me
O
CO2MeBr
Me
O
CO2MeMe
Br
+
major
O
CO2Me
Me
BrMe
Me
MeO
N
CO2MeMe
Me
MeO
N
Me
Me CO2Me
3:1
+
Me
Me
MeO2C Me
O N
Me
Me
Me
O NRO
Me
Me
Me
MOMO OH
Me
Me
Me
MOMO I
1. LDA/THF
2. HMPA/
NCCO2Me
H2
Rh(Al2O3)
Br2
MeOH/NaOAc
or Br2, CCl4
HN
EtOH
LiBHEt3
THF
1. ClMOM
2. LiBHEt3
I2, PPh3
imidazole
R=H, CH2OCH3
N
OMeMeO2C
N
OMeR1. Ca(BH4) THF, rt
2. CrO3/py. CH2Cl2, rt
MeNC, MeOH,
AcOH, 60°C N
OMe
OR
O
MeO
1. NaNO2, Ac2O, AcOH, 0°C
2. Na2CO3, CCl4, heat3. NaOMe, MeOH, 0°C
R=CH2OH, CHO
N
SO2Ph
CHO
OO
Me
Me
H2NN
SO2Ph
N
O
O
Me
Me N
SO2Ph
HN
O
O
EtHH
N
SO2Ph
N
O
O
EtHH
HO
HN
N
X
EtH
H
X=OCH2CH2O
X=O
PhH
Dean-Stark
pTsOH, PhH
Dean-Stark
BrCH2CH2OH
EtOH, Na2CO3
Et2O
tBuOK, 0°C
4N HClMeOH
Justine deGruyterBaran Group Meeting
05/23/2015JOC Year in Review: 1989
Electroreductive Intramolecular CouplingofKetones withOlefins.Shono,T.;Kashimura,S.;Mori,Y.;Hayashi,T.;Soejima,T.;Yamaguchi,Y.6001-6004.
Enantioselective ConstructionofaQuaternaryAsymmetricCarbonCenter:AVersatileSynthesisofα-Alkylα-AminoAcids.Ihara,M.;Takahashi,M.;Niitsuma,H.;Taniguchi,N.;Yasui,K.;Fukumoto,K.5413-5415.
Ph
Me
O
O OH
OMeR
Ph
MeO
O OH
ORMe
major
Ph
MeO
O OH
O
Ph
MeO
O OH
O
Me R>2equiv LDARX
>2equiv LDAMeI
+
Ph
MeO
O
MeEtCO2Me
O2N-C6H4CO2
MeEtCO2Me
Ph
MeO
O
NH2
MeEt
EtO2C NHCOCH2CO2Et
MeEt
(a) (COCl)2; (b) CH2N2; (c) AgOCOPh, MeOH; (d) HPLC; (e) LAH; (f) p-NO2PhCOCl, py., DMAP; (g) (PhO)2PON3, TEA, PhCH2OH; (h) Pd/C, cyclohexene; (i) KOH, 18-c-6; (j) HCl-EtOH; (k) EtO2CCH2COCl, DMAP.
a,b,c,d g,h,d
e,f i,j,k
OTMSOTMS O
Cl
Cl
O
NC
NCDDQ chargetransfercomplex
C-O bond formationTMS-shift
O
O Cl
Cl
OTMS
CN
NC
O
OTMS
NC Cl
Cl
O
OOTMS
Cl
Cl
OH
NC
NC
C-C bond formationTMS-shift
2,3-Dichloro-5,6-dicyano-1,4-benzoquinone(DDQ)OxidationofSilyl Enol EtherstoEnones viaDDQ-SubstrateAdducts.Bhattacharya,A.;DiMichele,L.M.;Dolling,U.-H.;Grabowski,E.J.J.;Grenda,V.J.6118-6120.
VinylOrganoboranes.12.Synthesisof(Z)-1-halo-1-alkenesviahydroboration of1-halo-1-alkynesFollowedbyProtonolysis.Brown,H.C.;Blue,C.D.;Nelson,D.J.;Bhat,N.G.6064-6067.
VinylOrganoboranes.13.AConveniet Stereospecific Synthesisof(Z)-1-halo-1-alkenesfrom1-alkynesvia(E)-1-alkenylboranederivativeswithhalogens.Brown,H.C.;Subrahmanyam,C;Hamaoka,T.;Ravindran,N.;Bowman,D.H.;Misumi,S.;Unni,M.K.;Somayaji,V.;Bhat,N.G.6068-6075.
VinylOrganoboranes.14.AStereospecific Synthesisof(E)-1-halo-alkenesfrom1-alkynes.Brown,H.C.;Hamaoka,T.;Ravindran,N.;Subrahmanyam,C.;Somayaji,V.;Bhat,N.G.6075-6079.
VinylOrganoboranes.15.Mercuration of2-alkenyl-1,3,2-benzodioxaborolesandBoronic Acids.AConvenientStereospecific ProcedurefortheConversionofAlkynesinto(E)-1-halo-1-alkenesviaMercuricSalts.Brown,H.C.;Larock,R.C.;Gupta,S.K.;Rajagopalan,S.;Bhat,N.G.6079-6084.
Notcovered(butworthmentioning):
R R 1
O
R 2R 2
OH
R
R1
C5H11
O
C5H11
OHMe
Me
O
Me
Me Me
HO Me
Me Me
OMe
Me Me
O
O
Me
Me
OH
Me Me
O
Me
Me
OHMeO
+ e
Selected Examples.
+ e, Bu4NBF4
DMF
80%
+ e, Bu4NBF4
DMF
80%
1. +e, 2.5F/mol
TMSCl, Et3N
2. H+
CHO1. +e, 2.5F/mol
TMSCl, Et3N
2. H+
Justine deGruyterBaran Group Meeting
05/23/2015JOC Year in Review: 1989
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