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JOC Year In Review: 1993Rohan MerchantBaran Group Meeting
04/18/2015
Ig Nobels 1993
Chemistry: James Campbell and Gaines Campbell of Lookout Mountain, Tennessee, dedicated deliverers of fragrance, for inventing scent strips, the odious method by which perfume is applied to magazine pages.
Mathematics: Robert Faid of Greenville, South Carolina, farsighted and faithful seer of statistics, for calculating the exact odds (710,609,175,188,282,000 to 1) that Mikhail Gorbachev is the Antichrist.
Statistics:Volume 581540 papers7957 pages
Publication record:Wipf, P. (9)Paquette, L. A. (9)Padwa, A (8)Olah, G. A. (8)Marshall J. A. (8)
Top Movies:Jurassic ParkMrs. DoubtfireSchindler's ListCool Runnings
Top Songs:I Will Always Love You by Whitney HoustonWhoomp! (There It Is) by Tag TeamCan't Help Falling In Love by UB40
Notable Events of 1993Cost of a gallon of gas ~$1.16Buckingham Palace opens doors to publicPentium microprocessor introduced by IntelWorld Wide Web was born at CERNX-Files debutsMichael Jordan retires for the first time15 June 1993 - Formula One world champion James Hunt dies (45)Shane Warne bowls "Ball of the Century" to Mike Gatting in the first Test at Old TraffordEU Farmers protest the reduction in agricultural subsidies due to Maastricht Treaty
Top 5 Most Cited Papers:
Design, Synthesis, and Control of Conducting Polymer Architectures–Structurally Homogenous Poly(3–Alkylthiophenes)McCullough R. D., Lowe R. D., Jayaraman M., Anderson D. L. J. Org. Chem. 1993, 58, 904–912757 citations
An Improved Procedure for the Preparation of the Dess–Martin PeriodinaneIreland R. E., Liu L. B., J. Org. Chem. 1993, 58, 2899641 citations
New Nitric Oxide–Releasing Zwitterions derived from PolyaminesHrabie J. A., Klose J. R., Wink D. A., Keefer L. K., J. Org. Chem. 1993, 58, 1472–1476476 citations
A Convenient Reduction of Amino–Acids and their DerivativesMcKennon M. J., Meyers A. I., Drauz K., Schwarm M., J. Org. Chem. 1993, 58, 3568–3571407 citations
Analysis of 2 C–13 NMR Correlations for Determining the Stereochemistry of 1,3–Diol AcetonidesRychnovsky S. D., Rogers B., Yang G., J. Org. Chem. 1993, 58, 3511–3515358 citations
JOC Year In Review: 1993Rohan MerchantBaran Group Meeting
04/18/2015
Me
MeMe Me
NH
CNHN
NH
1. Hg(NO3)22. NaBH4
39%
Me
MeHN
NHMe
HCl, Δ59%
Me
MeHN
NMe
HO
1. O2, Pt, EtOAc2. H2, Pt, 0 °C
Me
MeHN
HN
NaOH, MeOH,reflux, 48 h
97%
Me
MeHN
HNOHLiAlH4,
THF96%
33%
Me
MeHN
MeHNHCl, MeOH87–94%
Alloaristoteline
Serratoline
Aristotelone
Heathcock; JOC, 1993, 58, 564–568
TMSO
1. C6H6, reflux2. NaBH4, CeCl3
60% (2 steps)
OHH
OTMSOH
OHH
OTMS
KH, 18–Cr–6,THF, reflux
80%
OH
O
Devaux; JOC, 1993, 58, 2349–2350
O
O
First synthesis of tricyclic core of Vinigrol
oxy–Cope
O
MeMe
H
O
O
O
chromatography separation of diastereoisomers
Me Me
Me
LiAlH4
MeMe
H
OH
R-(+)-isomer
1. MnO22.
LDA, CdCl2
MeMe
MeMe
H Me
O
OMeOH,
BF3•Et2O, rt
83% Me
O
O
MeMe
OMe
HMe
Me
OMeH
MeO
O
Me
Me Me
OMeH
toluene,µw, 2.5 h97%
Me
Me Me
98%
Me
O
OMe
OMeMe
H
OHMeOH
86%
NH MeLi,
THF55%
racemic
O
O
Me Me
Me
Cl
C6H6, Et3N
(63% 2 steps)
MeO2C
(+)-Longifolene
Fallis; JOC, 1993, 58, 2186–2195
CO2HI
KBrO3,H2SO4
93%I
OO
OOH
Ac2O, 0.5% TsOH,80 °C, 2 h
91%I
O
OAcOAc
OAc
In the absence of TsOH, difficult to obtain reproducible results for acetylation
Ireland; JOC, 1993, 58, 2899
DMP
O
OMe
Me
use oxone instead
JOC Year In Review: 1993Rohan MerchantBaran Group Meeting
04/18/2015
NH
HOMe
NH
CHO MeClMg
THFquant. TFA, (CH2OH)2,
150–155 °C
26%NH
MeMe
Me
N
NH
N
Me
MeMe
H
H
NH
NH
H
Me
MeMe
H
H
Yuehchukene
Sheu; JOC, 1993, 58, 5784–5787
N Cl
NO
N
Me
NH
Me
N Cl
NO
N
Me
N
Me
N Cl
NEt
NMe
O
NN Cl
EtN
N
NHMeO
N
NEt N
N
OMe
N
NEt NN
OMe
A
B
LiHMDS/THF, –10 °C, 2h 17% 76%
A B
KOtBu/THF, rt, 5 min 54% 22%
Proudfoot; JOC, 1993, 58, 6996–7000
conditions
name rxn
Conditions
1. nBuLi2. DMF3. 0.1 N HCl
HO
R
TMSMe
9–BBN
1.
2. 2–aminoethanol50%
R = H; 80%R = Me; 81%
HOTMS
Me
R
MeR
H2SO4R = H; 93%R = Me; 86%
Me
R
Me
RRMe
RMe
MeR
H
HR = H; 50%R = Me; 13%
benzene, reflux
Wang; JOC, 1993, 58, 1651–1652
MeO
Me
O
OH MeO
O
O
OMe
OMe
50%, 94% ee
1. NaHMDs2. 1, THF
Davis; JOC, 1993, 58, 1751–1753
MeO
O
O
OMe
OMe
OH
MeO
OOMe
OMeHO
Me Me
ClCl
SO2
ON 1
asymmetric hydroxylation
JOC Year In Review: 1993Rohan MerchantBaran Group Meeting
04/18/2015
PdLn
N
NI
Me
H
H
CO2Me
5% Pd(OAc)2,K2CO3, DMF,nBu4NCl, 80 °C
N
N
HCO2Me
Me
H
H
84%N
N
CO2Me
HH
Me
expected product not formed
N
NH
HMe
MeO O
PdLL
H N
NH
H
MeO OH
H
PdLnMe
N
N
HCO2Me
Me
H
H
Rawal; JOC, 1993, 58, 5583–5584
"unexpected Heck"
NH
CO2Me
N
Ph
thermodynamic product
Pd/C, H2,MeOH
NH
CO2Me
N
OH
OH
67% (2 steps)
N
N
O
H
O
Strychnine
10% HClO4/THFrt, 5 h
51 % (2 steps)NH
CO2Me
BnN
CHO
Me3SI, tBuLi, THF,
–20 to 45 °C
NH
CO2Me
BnN
O reflux
NH
NBn2
NH
NHBn
CO2Me
CHO
BF3•Et2O,toluene,
110 °C, 18 h
NH
CO2Me
BnN
Kuehne; JOC, 1993, 58, 7482–7489,Kuehne; JOC, 1993, 58, 7490–7497
OMe
MeO
OMe
OMe
R
OH
R = Ar, Alkyl Het. Ar
R
N3(PhO)2PON3, DBU,toluene, 0 °C to rt
R
OPO(OPh)2
N
HN
N380–90%, ~95% ee
O
OH
99.6% ee
O
N3
O
(PhO)2PON3, DBU
(PhO)2PON3, PPh3(Mitsunobu cond.)
EtO2CN NCO2Et
91% yield(97.5% ee)
1%
81% yield(82% ee)
6–8%
Grabowksi; JOC, 1993, 58, 5886–5888
Practical Alternative to Mitsunobu Conditions for activated alcohols to azides
silica–gel filtration
2 x FCC,1 distillation
Name Rxn
JOC Year In Review: 1993Rohan MerchantBaran Group Meeting
04/18/2015
OHTHPOBnN
O NBn
OTHP
Weinreb; JOC, 1993, 58, 4945-4951
320 °C,DCB
BnN
O
OTHP
BnNBnNBnN
O
THPO
H
H H
44%
TsNBnN
OHH
H H
TMS
FeCl3, CH2Cl2,–78 C to rt
TsNHH
NBn
TMS
H61%
TsNHH
NBnH
Sarain A core
Al(Me)3 (3 eq.)CH2I2 (2 eq.),
CH2Cl2, rt OH71%
Price; JOC, 1993, 58, 3589–3590
Me
Me
Me
OR
A: Et2Zn, CH2I2, Et2O, rtB: iBu3Al, CH2I2, CH2Cl2, rtC: Sm/Hg, CH2IX, THF, –78 C to rt
Me
Me
Me
OR
Me
Me
Me
OR
Me
Me
Me
OR
R A B CH 74 1 98
Bn 97 67 75
2 76 0HBn 1 0 0
H 3 4 0Bn <1 0 0
Yamamoto; JOC, 1985, 50, 4412–4414Org. React. 2001, 58, 9
complementary to the usual
Simmons–Smith cyclopropanation
N
MeO2C
NBn
CO2Me
ClN
MeO2C
NBn
CO2Me
H
Hi. LDA, THF, –70 °Cii. HCl, rt
33%
Bosch; JOC, 1993, 58, 7756–7767
N
NH
OH
H
MeO2C H Me
O
N
NH
MeO2C H Me
OClhν,
MeOH–H2O, 15 min
55%N
HNH
MeO2C H Me
Et3N61%
Cl
OCl
N
NH
H
H
MeO2C H Me(±)-2,7-Dihydropleiocarpamine
1. Lawesson's reagent2. NiCl2, NaBH4, MeOH
N
NH
H
H
MeO2C H
O
Me
Et3SiH–TFA(50%)
(30 % 2 steps)
NiCl2
Back; JOC, 1993, 58, 2407–2413
Me
MeMe
Me
Me
HCl
NaSPhMe
HPhS
NiCl2, NaBD4,MeOD
LiBEt3D
Me
HD
NaBH4, ROH Ni2B + H2
RSR' Ni2B RH + R'H
Stereoretentive!
mild desulfurization conditions
OH
JOC Year In Review: 1993Rohan MerchantBaran Group Meeting
04/18/2015
OH
OH H
O BF3•Et2O, 23 °C
71% OH
HO
OBz
OH
HOBz
OO
Overman; JOC, 1993, 58, 2468–2477
NaOMe, MeOH
83%
O
OOHMeO2C
dr = 10–12:1H
H
O
O
H
HMe
BrHH
Br
(±)-kumausallene
R
OMeOOH Li MeMg(HMDs)2
2 x LiHMDs + MeMgCl
75%toluene R
MeOOH
NClR =
Weinreb's procedure provided the methyl ketone in 71 % yield, along with several impurities (0.5-1%) which were not
easily removed without a yield penalty
The new reagent provides clean product with complete suppression of impurities
Reider; JOC, 1993, 58, 3731–3735
R NH2
O PhI(OAc)2,KOH, MeOH R
HN OMe
OR = Alkyl, Ar, Het Ar
analogous to Curtius rearrangement
Moriarty; JOC, 1993, 58, 2478–2482
70–90%PhI(OAc)2
KOH,MeOH PhI(OMe)2
R N
OIPh
OMeR NH
OIPh
OMeMeO
C N R
–PhI–MeO– MeOH
RHN OMe
O
O
OH
O
AcO
HO AcOOBz
O
OMeO
Ph
NHBz
OCO2Bn
Me
O
AcO
AcOOBz
O
OMeO
Ph
NHBz
OCO2BnMe
MeMe
DAST,CH2Cl2
Chen; JOC, 1993, 58, 4520–4521
OTroc
O
HO
HO AcOOBz
O
OMeO
Ph
NHBz
OH
Me Et2NCF2CHFCl, CH2Cl2
(Yarovenko reagent)
OTroc
OHO AcO
OBz
O
OO
Ph
NHBz
OH
Me
OTroc
OHO AcO
OBz
O
OO
Ph
NHBz
OH
MeMe F
47%
13%
Chen; JOC, 1993, 58, 2927–2928
MeMe
MeMe
MeMe
NN
SO2Ph
SO2Ph
RM NHN
SO2Ph
NNR
SO2Ph
Padwa; JOC, 1993, 58, 2061–2067
BA
NaH 100 0MeMgBr 0 100nBuMgBr 0 100sBuMgBr 0 100PhMgBr 0 100tBuMgBr 12 88MeLi 50 50nBuLi 17 83sBuLi 67 33tBuLi 33 67
RM A B
DDQ
NNR
SO2Ph
possible method to get around alkylation selectivites
for pyrazoles?
esters to methyl ketones
OBz
Prins cyclisation – Pinacol rearragement
7 7
7–epi Taxol
19
80–90%
10
Et2N
F F
Cl
F
Yarovenko reagent
"relatively safe fluorinating agent that is easy to use"
–EROS
JOC Year In Review: 1993Rohan MerchantBaran Group Meeting
04/18/2015
OOBn
Me MeO
HOi. DDH, aq. MeCNii. CSA, CH2Cl2
75%, 15:1 dr
O
OO
OHOBn
Me MeOxidative rearrangement
Albizati; JOC, 1993, 58, 291–293
O
OO
MeO
MeMe
OMeTrioxa-Tricyclic Subunit
of Saponaceolides
O
Me
1. CH2(CO2Et)2, Na, EtOH2. KOH, HCl
O
MeOH
OPPA,
AcOH, 100 °C O
O
MeLDA (2 eq.),THF, –78 °C
O
Me
OFeCl3,
DMF, –78 °CO
Me
O
Me
HO1. THF–HMPA, –78 °C2. THF, 0 °C
Ph3P CH2
H2C CHMgBr
KHMDs,THF, Δ
OH
HMe
Paquette; JOC, 1993, 58, 4245-4253
H
H
H
MeMeO
H
H
H
H
MeMe H
CO2H
Me
N
S
O
OO
OMsMe
OTBDMSH
DMSO,rt, 3 h N
S
O
OO
XMe
OTBDMSH X = Cl, 90%
X = Br, 85%X = I, 75%
Altamura; JOC, 1993, 58, 272–274
O2N O2N
I
NIS, TfOH, rt, 86%
NIS, Ag(OTf), 150 °C; 45% F3CS
O
O OHI TfO
Olah; JOC, 1993, 58, 3194–3195
E1
E2
1. NaH2. CuX2, DMSO, 40 °C
X = Cl/Br
E
EX
E1/E2 = EWG
70–90%tolerates double and triple bonds along with allylic and benzylic moeities
Dai; JOC, 1993, 58, 4596–4598
Cerorubenic Acid-111
40%
61% (2 steps)
71% (2 steps)
80%
88%
CaX2,
for highly electron deficient aromatics
Bn2N CO2HBn2N
OsO4 (cat.)Jones reag.acetone/rt
Presence of basic nitrogen does not interfer withe the reaction.
Weinreb; JOC, 1993, 58, 4745
65%
Mildly acidic conditions – protection of basic nitrogen as ammonium salt
mild halogenation conditions
NH
NH
O
MeMe
O
DDH/DBH O
HO
O OMe
OBnMe
via
intramolecular oxidative coupling
applied to other allylic and benzylic systems
No need for chromatography
"very reactive superelectrophile"
"widely used as a disinfectant used for
drinking water purification"
JOC Year In Review: 1993Rohan MerchantBaran Group Meeting
04/18/2015
TMS
TMS
O
OTMS
TMS
O
O
IBuLi, TMEDA
90% 1. HCO2H, CuSO42. (MeO)2POCH2CO2Me, tBuOK
TMS
TMS
CO2MeAcO SiMe3
Pd(OAc)2, (iPrO)3P
TMS
TMS
CO2Me
KF, DMSO
[3+2]90%
95%
CO2Me 81%
5% CpCo(CO)2,136 °C, hν
TMS TMS
CO2MeTMS
TMS
decane, 175 °C
75%[2+2+2]
[4+2]
TMS
TMSCO2MeH
H
TMS
TMSCO2MeH
H
75%15%
Malacria; JOC, 1993, 58, 4298-4305 Some useful modifications
MeN Me
N
O OPh
OHi. 1, Additive, THFii. PhCHO N
LiPhPh
Me Me
N SHNBS, MeOH
N SOMe
O
H
H
O
SSPivO
H
H
O
SSPivO
74%
Trost; JOC, 1993, 58, 1579–1581
i. KH, THFii. 2, toluene, CuSO4, 110 °C
Additive ee (%)None 24LiCl (0.5 eq.) 78
1
Simpkins; JOC, 1993, 58, 533–534
2
Me
OHOH
AcCl (1.2 eq.), Base (2.0 eq.)CH2Cl2, –78 °C
Me
OHOAc
Yamamoto; JOC, 1993, 58, 3791-3793
Bulky bases (iPr2EtN or collidine) give better selectivity than Et3N, pyridine
N
O
OHO2C
NNHTs
DCC N
O
O
O
O
N2
RH = Ar/Alkyl amine, phenols, thiophenols, peptides
3,THF/DMFRH R
O
N2
Badet; JOC, 1993, 58, 1641–1642
3
Extends to other acyl chlorides and silyl chlorides as well
iPr2EtN 86 95.7:4.3collidine 92 98.5:1.5
base yield (%)
1° OAc: diacetate
Ph
O
O Ph
O
H
SnCl2•2H2OCH2Cl2, rt naphthalene; 53% (2 h)
C60; 63% (3 h)
Roskamp; JOC, 1993, 58, 4142–4143
no promoter; 38% (16 h)
enone formation while avoiding oxidation step
mild diazoacylating agent
79% (2 steps)
OH
bench stable
FYI!
retro 4π e-
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