EROS: Vol I and II
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Acetylmethylenetriphenylphosphorane
Will Gutekunst
Aluminum Bromide
O
Ph3P
N
N
140C
O
O
OH
Me
O
i-Pr
AlBr3, hv
i-Pr
O
AlX2
i-Pr
67%
DCM, rt
Me
Cl
Chem. Ber. (114) 3146
JOC (56) 5745
O
Ph3P
R N3
R = Ts, Bz, Ar (slow)
R = Alkyl, no reaction
N N
Me
DCM
"sludge catalyst"
N R
AlBr3, tBuBr
50 -60C, 1h
65%
Me
JOC (31) 1587; JOC (37) 3213
R
O
Cl
R
N
H
N
Ph3P
N
Br
NAr
Me
B Et
Me
Ar
Me
DCM
Et
Me
Me
Et
AlBr3
CCl4, RT
95%
B Et
Me
Br
Alumina
Chem Comm (1972) 71
Bu
I
35C, 2 h
85%
H
I
H
I2 activated
alumina
Aluminum Hydride
H
Bu
I
JOC (53) 4477
AlH3
N
n
HX
alumina (or silica)
H
70-92%
n
n = 1-4
H
DCM
Tetrahedron (24) 4489
X
HX can be generated in situ by TMSX, (COX)2, SOCl2, etc.
JACS (115) 3071
Ammonium Peroxydisulfate
Aluminum
Lumazine to pterin
O
N
MeN
O
N
Me
N
Al(HgCl2)
OEt
aq MeOH-NH3
81%
O
O
N
MeN
O
Me
Me
N
Me
N
H
Heterocycles (24) 1565
Me
Me
Na2S2O8
NaCN, H2O
80C, 68%
Me
CN
O
Me
Me
Tet Lett, (27) 4215
EROS: Vol I and II
Baran Group Meeting
Ammonium Sulfide
(NH4)S
dioxane/
H2O
Me
O
Benzene Sulfonyl Bromide
(NH4)2S
O
O
(NH4)S
H
dioxane/
H2O
26%
CONH2
CO2H
O
O
Br
dioxane/
H2O
Benzene Sulfonyl Isocyanate
Me
O
Me
ultrasonically
stimulated
baker's yeast
MeO2C
Y
NSO2Ph
-COX
NSO2Ph
R
R
30-71%
Y
R1
CO2Me
X
H
Me
R2
Me
31%, 96% ee
R1
PhSO2NCO
Me
Y
X
R2
Y
O
R1,R2 = H, alkyl, arl
X,Y = H, OR; O; S
Me
Y
NSO2Ph
HO
(racemic)
O
X
X = S, O
Y = alkyl, aryl, O, NR2, S, CO2R
Me Me
Benzenetellurinic Anhydride
JACS (110) 604
O
O
PhSO2NCO
X
Also converts alcohols, thiols, amines and alkynes
into primary amides
R
Me
Me
SO2Ph
JCS Perkin 1 (1983) 2417
Me
O
N
NH2
dioxane/
H2O
20%
NH2
CO2Me
Me
THF, aq NaOH
Bu4NOH
quantitative
O
Baker's Yeast
Me
Ph
Ph
N
H
O
dioxane/
H2O
60%
Me
3.5 eq PhSO2Br
CONH2
(NH4)S
Me
NH2
(NH4)S
Cl
Will Gutekunst
baker's yeast
pH 7.5
O
O
O
H OGlu
baker's yeast
pH 6.4
O
MeO2C
O
10 mol%
[p-EtOC6H4Te(O)]2O
O
H
MeO2C
OH
Me
Me
O
reflux AcOH
85%
O
Me
Tet Lett (27) 6099
OH
Chem Comm (1991) 825
Bis(acetonitrile)chloronitropalladium(II)
Benzene Sulfonyl Azide
Pd(MeCN)2(NO2)2
O2
PhSO2N3
ether
N
Me
71%
C8H17
PhSO2N3
MeCN
N
Me
NSO2Ph
J. Het. Chem (24) 1413
O
reflux
O
NO2
C8H17
C8H17
180C
O
NSO2Ph 0.1 mm
N
O
SO2Ph
JOC (31) 2847
Only terminal olefins, long reaction
times, stoichiometric in Pd
Toluene
Acetone
11:1
1:7
Organometallics (3) 1479
EROS: Vol I and II
Baran Group Meeting
Bis[N-(p-toluenesulfonyl)]selenodiimide
Bis(allyl)di-µ-chlorodipalladium
O
Will Gutekunst
Me
OMe
1. LDA, THF
2. Pd allyldimer
H
O
Me
Me
Cl
OMe
H
Pd
TEA or HMPA
78%
Cl
Seo
Na
DCM
TsN
Pd
Cl
TsN Se NTs
JOC (45) 5193
Bis[N,N-bis(trimethylsilyl)amino]tin(II)
I
OTMS
OTMS
TsN Se NTs
(TMS)2N N(TMS)
2
Sn[N(TMS)2]2
Me
Sn
NHTs
Me
82%
Me
I
PhH
TsN Se NTs TsHN
51%
Me
TsN Se NTs
Me
JCS Chem Comm (1978) 192
Me
Me
Me
Me
Me
51%
Bis(cyclopentadienyl)mehylzirconium Tetraphenylborate-Tetrahydrofuran
Me
N
Me
N
TsN Se NTs
Me
Me
cat. Cp2Zr(Me)BPh4
H2
H
NHTs
Me
Se
R
NTs
R
TsN Se NTs
Me
NTs
68%
Me
Prepared from SeOCl2
Me
Me
JACS (98) 269
Bis(dimethylglyoximato)(methyl)-(pyridine)cobalt(III)
Me
Me
Me
Me
O
CoI(dmgH)
Me
Me
Me
2
Me
OH
80%
Me
NHTs
Prepared from chloramine-T
JACS (111) 778
Me
H
O O
N
N
Co
N
O O
H
NHTs
Bis[N-(p-toluenesulfonyl)]sulfodiimide
TsN S NTs
CoX
Ph
Ph
OH
hv
OH
PhH
94%
Me
Me
OH
PhH, 10C
91%
TsHNS
NTs
Ph
PhH
reflux
TsHNS
Na2SO3
NTs
DME
94%
Liebigs Ann Chem (1975) 1725
Me
TsN S NTs
Cl
Tet Lett (32) 243
Cl
S
PhH, RT
75%
Bis(pyridine)iodonium(I) Tetrafluoroborate
NTs
NTs
Tet Lett (1966) 1671
I N
Me
BF4Me
2 HBF4, DCM
-60C, 30 min
78%
Me
I
F
Me
Me
TsN Te NTs
H
Me
O
JOC (56) 2234
NHTs
OH
py
N
Ph
PhMe, reflux
100%
Me
Me
Me
Me
H
NTs
JOC (56) 6468
EROS: Vol I and II
Baran Group Meeting
Boric Acid
Bis(trimethylsilyl) Peroxide-Vanadyl Bis(acetylacetonate)
O
30 mol% (TMSO)2
OH 10 mol % VO(acac)
2
Me
Me
OH
OH
30 min
Me
DCM, rt, 5h
85%
Me
Will Gutekunst
Me
R
OEt
O
R
OEt
80%
O
O
Me
Me
7h
OH
OH
B(OH)3
170C, 1.5h
OEt
Me
70%
Me
Me
O
OH
Me
OH
Ph
+
Me
68%
N
H
0.3 eq B(OH)3
reflux mesitlyene
CO2H
1.1 eq
N
82%
O
4h
Me
OH
10 min
Me
81%
80%
Me
Ph
O
OH
Me
Me
Boron Trichloride
NHMe
TL (24) 3741
ArCHO
Borane–Pyridine
NHMe
TEA, PhH
- Mild reducing agent with greater hydrolytic stability than NaBH4 in protic solvents and
higher solubility in aprotic organic solvents.
- Inexpensive and less toxic alternative to NaCNBH3 for reductive aminations
N
BH3
2-hexene
3-hexene
BR2
Me
Me
BR2
Me
Me
JACS (88) 1433
Me
Me
3
Me
Br
Br2
hv
Me
B
2
Me
Me
H2O
Me
Me
Me
Me
Me
1. Br2, H2O
hv
OH
2. [o]
46%
Me
Me
B
Me
Me
Me
Me
JACS (89) 561
86%
Me
HO
4 h, 67%
B
BF3(g)
wet DCM
Me
RT, 10 min
90%
O
camphor
All other conditions/LA's failed
J Chem Soc Perkin 1 (1973) 2109
Me
Me
Me
OH
JACS (93) 1025
Ph
Cl
F2N
Me
NF
Br
20C, 4h
94%
J Chem Soc (1957) 2174
JACS (64) 1032
3%
F
BF3
Me
82%
5%
OAc
BH3, then
diglyme, 160C
Br
Me
2-fluoropropane
BF3
92%
BR2
Me
JACS (100) 4842
Boron Trifluoride
HB; 150C, 16h
Me
R
JACS (127) 5766
Me
HB; 150C, 16h
NHMe
O
Borane–Tetrahydrofuran
1-hexene
Ar
RCN
OH
TBDMSO
2. NaOH, H2O2
83%
HB; 150C, 16h
OH
Formylation with isocyanides. Similar ortho selectivity observed with phenols.
1. 1 eq Py-BH3
0.5 eq I2, RT
TBDMSO
Me
N
BCl2
BCl3
BF3
DCM
68%
Ph
Cl
F2N
F
EROS: Vol I and II
Baran Group Meeting
Boron Trifluoride–Acetic Acid
Ph
Will Gutekunst
Bromomagnesium Diisopropylamide
Ph
Ph
Bu3Sn
BF3•2AcOH
OH
97%
Me
Me
O
Ph
TMSCl
Me
Me
Boron Trifluoride Etherate
O
CO2Me
C5H11
Me
Me
97:3
O
5
Me
mix of cis and trans
OMe
O
Tol, 0C
80%
Me
Chem Comm (1967) 984
Mg Br
BrMgN(TMS)2
Me
Bromine
OMe
Me
Br
Otherwise, very similar to bromomagnesium diisopropylamide
Br2
Coll. Czech. Chem. Comm (27) 1927
S
S
Br2 (2 eq)
t-BuNH2 (4 eq)
OH
Br
OH
Br
MeO
Br2 (1 eq)
t-BuNH2 (1 eq) MeO
Br
O
OH
Br
Br
Tol/DCM
-70C to rt
87%
Tol/DCM
-70C to rt
75%
O
Br2
Me
Me
Br2, Ag2O
O
Me
Me
Me
Et
Me
OH
O
Me
rt, pentane Me
"one ethereal
product"
73%
OTMS
Me
4-BrPhSO2N3
MeCN, 63C
83%
KOtBu
53%
O
S
Me OMe
Tet Lett (27) 4701
KOtBu
Br
65%
hv, -15C
81%
B(OR)2
Me
Me
NSO2Ar
Br
B(OR)2
Bromo(o-tolyl)bis(triethylphosphine)-nickel(II)
Et3P
OMe
O
Me Br
O
S
R
JACS (108) 4568
Et
Ni
NSO2Ar
O
TEA
Br
Me
4-Bromobenzenesulfonyl Azide
4-BrPhSO2N3
MeCN
hv, -15C
Ph
JACS (86) 3905; Tetrahedron (40) 2643
Me
Br
O
S
R
85%
Ph
rt, dark
75%
OTMS
Br
hv, -15C
Bromine–Silver(I) Oxide
Br2, Ag2O
pentane
S
Br O
R
O
S
JOC (32) 2358; JOC (58) 3877
OH
O
H2O
S
Bromine–t-Butylamine
OH
Coll. Czech. Chem. Comm. (38) 3499
Bromomethanesulfonyl Bromide
Br
Me
Me
Me
+
N(TMS)2
CO2Me
C5H11
PhH
35%
5
Me
Bromomagnesium Hexamethyldisilazide
O
BF3•OEt2
TMSO
Me
Et2O
TEA, HMPA
95%
Me
Tet Lett (24) 4591
Me
TMSO
(iPr)2N MgBr
Br
PEt3
I
MeO
80C, 88%
MeO
Br
80C, 68%
Br
3 mol% cat
Bu4NCl, PhH
3 mol% cat
Bu4NBr, PhH
3 mol% cat
Bu4NCl, PhH
Cl
Br
80C, 96%
Cl
JOC (45) 1930
EROS: Vol I and II
Baran Group Meeting
Will Gutekunst
Carbon Monoxide
Bromotrimethylsilane
O
TMSBr
DMSO, iPrNEt2
Me
(most yields 40-60%)
Heterocycles (31) 987
Br
CHCl3, RT
85%
CO2H
O
O
HSiEt2Me, CO
4 mol% Co2(CO)8
HSiEt2Me, CO
4 mol% Co2(CO)8
OSiEt2Me
O
RT, PhH, 20h
88%
RT, PhH, 20h
81%
OMe
OSiEt2Me
t-Butyllithium
BnO
JACS (111) 7938
CO (41 atm)
5 mol% Co2(CO)8
10% 3-hydroxypyridine
O
OH
BnO
60C, MeOH
86%
t-BuLi
I
CO (1 atm)
cat. Seo
94%
I
JACS (110) 7230
n-Butylnitrite
BuONO
C5H11
Me
THF, RT
95-99%
R = butyl, hexyl, octyl, cyclohexyl
N
H
(s-Bu)3B
JACS (93) 6344
C5H11
92%
O
Me
Me
O
PrOH, 73%
N
N
Me
Carbon Dioxide
77%
Chloramine-T
N
Me
Na
OH
SO2NCl
R2
CO2H
77%
O
N
Me
H
Me
NHTs
R1
+
97:3
4:96
Chloramine-T
DCM, RT
Me
CO2H
M = Na (150C, 80% yield)
M = K (210C, 48% yield)
Me
Tet Lett (33) 85
Me
CO2
S
TMS
CsF, MeCN
Me
Chem Lett (1992) 1137
OH
S
nitrosodimer
O
Me
OM
(s-Bu)3COH
125C
then H2O2
87%
N
Tet Lett (1969) 4001
H
Me
1 atm. CO
diglyme
R
N
H
S
Me
JOC (64) 2164
Cesium Fluoride
Me
BuONO, PhSiH3
10 mol% Fe(acac)3
CO2Me
O
R
R NH2
O
R1
OR
R2
Chloro(cyclopentadienyl)dimethyltitanium
N
H2O
CpTiMe2Cl
NH2
Carbon Disulfide
O
CS2, MeOLi;
MeI
46%
OSiEt2Me
OMe
Me
cis halolactonization
H
N
OSiEt2Me
Ph
O
THF, RT
N TiCpCl
Ph
N TiCpCl
Ph
Ph
96%
R1
iPrCN
NH
81%
OMe S
O
iPr
R2
SMe
Chem Lett (1982) 123
(catalytic with CpTiCl3) JACS (114) 5459
EROS: Vol I and II
Baran Group Meeting
Chlorodimethylsilane
Me
BuLi
ClSiMe2H
Ph
3-Chloro-1-hydroxytetrabutyldistannoxane
0.2 mol %
Pt[(CH2=CH)Me2Si]2O2
RT
Me
Ph
N
NH2
HMe2Si
Ph
Me
SiMe2H
Ph
76% overall
HMe2Si
O
+
HMe2SiN
Similar chemistry with chlorodiisopropylsilane and chlorodiphenylsilane
O
Cl
Cl
Cl
0C to RT
34%
Bn
+
OH
Cy
80%
cy
Cl
AgBF4
DCE
Me
N
Me
Me
O
Bn
R B
Cy
Me
N
O
Me
Me
Me
Me
O
K2CO3, 0C;
PhH 80C Cy
N
N
O
Me
Me
KCN
Cy
N
O
NC
H
Me
80C
>90%
H
H
MeO
TMS
Me O
Me
H
sBuLi, THF
-78C to RT
40%
MeO
(yields generally higher)
H
Me
O
Me
Me
OH
Cl
hypochlorite
N
H2 Cl
N
O
O
OAc
95%
EtOH
87%
R = Me, 93%
R = vinyl, 90%
EtO
OAc
+
Liebigs Ann Chem (1981) 610
CyN
N-Chlorosuccinimide
H
O
Me
H+
NCS
Cl
THF
89%
N
Me
H
N
Me
CHCl3
NaHCO3
76%
N
N
Me
O
Tet Lett (29) 2405
Chlorosulfonic Acid
O
MeO
Ph
Organometallics (1) 893
O
NCS
Me
H
93%
OEt
OAc
Me
O
Me
TMS
B
Me
O
OAc
1-Chloroethyltrimethylsilane
Cl
BuLi
-78C
Me
Me
O
R
rt
Organometallics (4) 1687
N
Helv Chimica Acta (55) 2198
Me O
H2O
1-Chloro-1-nitrosocyclohexane
Me
Me
tBuOK
H
B
Me
95%
Me
Me
Me
O
R
Cl
Me
O
Helv Chimica Acta (55) 2187
Cy
+
OR
I
Cl
Me
O
R1
H2O
O
cat.
R2
+
Chloromethyllithium
trans:cis = 99:1
C-(1-Chloroethyl) N-Cyclohexyl Nitrone
N
HO
OH2
JACS (103) 2443
O
OR2
Usually, catalyst loadings are below 1 mol% (some examples at even 0.05 mol%).
Also catalyzes acetal formation/deprotection and THP/silyl deprotection.
Bn
Me
Y Sn O Sn R
R
R R X
O
cat.
R2
O
JOC (55) 3438
BuLi
THF/Hex/HMPT
rt, 1 h
LiTMP
HO
OR1
Si
Me2
2-Chloroethyl Chloromethyl Ether
O
R
X
R R
Sn O Sn Y
"extremely stable in air and to moisture and thus can be handled and stored in the open air. Because this
compound is not volatile, it is virtually nontoxic under the usual conditions."
Ph
SiMe2H
R
O
OH
Sn
Bu Bu Bu Bu
Sn
NH2
Me
Rh cat.
N
Si
Me2
Cl
iPr
Me
Ph
O
OSiMe2H
OH
HMe2Si
R
Pt cat.
H2O2
KF
iPr
N SiMe2
Me
R
Will Gutekunst
O
O
O
ClSO3H
55%
Ph
O
O
O
O
O
Ph
JACS (105) 2414
EROS: Vol I and II
Baran Group Meeting
Nu
Chlorosulfonyl Isocyanate
130C
SO3 + ClCN
Cl
Chlorosulfonyl Isocyanate (cont.)
O O
S
N
N
H
O
cycloaddition
CSI, Na2CO3
DCM, RT
OBn
-CO2
SO2Cl
O
R
DMF
SO2Cl
N
H
R
CN
Me
CSI
Ph
Ph
H
N
N
H
Me
N SO2Cl
< 0C
Cbz
CBz
+
NH
Me
Me
Me
82%%
Me
O
O
Ph
OBn
+
1:1
CSI, Na2CO3
DCM, -78C
SO2Cl
Ph
O
O
Me
72%
> 0C
NH
8.4:1
CSI, Na2CO3
DCM, RT
OBn
R = tBu, Cy, ClCH2CH2, Bn, PhCH=CH, 1-naphthyl
O
N
H
Cbz
90%
O
R
OH
Cbz
O
}
R
O
CSI
O
Will Gutekunst
N
H
CBz
Tet Lett (41) 5073
N SO2Cl
O
Chlorotrimethylsilane
Ph
Me R
Me R
CN
STol
1. CSI
X
X
2. DMF
X = O, NH, S
Ph
Me
O
2. H2O,
R1 R2
Ph
CSI
O
Chlorotris(triphenylphosphine)rhodium(I)
NH
H
O
O
Me
O
R1
R2
CSI
R3
R4
O
O
PhH/DCM
R1
R3
-10C
R2 R4
10 min
major
O
O
R1
Me
NSO2Cl
R2 R4
1. CSI
Me
R3
Me
Me
2. H2O, OH- Me
43%
Me
Et
Et
CSI
DCM, 0C
95%
ClO2SN
5% RhCl(PPh3)3
1 eq DPPA
Me
Me
Me
THF, RT
90%
DPPA
Ph3P Rh CO
PPh3
Cl
Me
+
O
PhO P
NCO
PhO
only primary aldehydes
O
Ph3P Rh L
Cl
PPh3
N
H
JOC (57) 5075
Chromium(II) Acetate
Et
Et
Me
Me
+
94%
95%
O
O
O
NSO2Cl
O
R2
R1
CN
HO
Me
O
TMSCl, NaI
MeCN
Me
Tet Lett (22) 3551
N
OH-
HgCl
R
O
HN
1. CSI
2. DMF
HgCl
TMSCl, NaI
MeCN
Me
STol
R
X = O, NH, S
H
N
NC
CN
1. CSI
Et
O
Et
N
O2S O
Et
Me
Me
H2O, HCO3-
Et
O
O
Cl
MeOH,
MeO-
Et
Et
HN
CO2Me
SO3Me
HO
O
JOC (37) 196
HO
Cr(OAc)2
EtSH
Me
O
HO
Me
I
DMSO
O
Me
Br
H
O
Can also use CrCl3 with Zn(0)
O
Cr(OAc)2
BuSH
HO
Me
DMSO
80% O
(5 eq Cr and 7.5 BuSH)
JOC (17) 290
H
EROS: Vol I and II
Baran Group Meeting
Copper(I) Phenoxide
Cobalt(II) Acetate
O
1-hexene (2 eq)
Co(OAc)2
O
OMe
MeO2C
4 PhOCu + CS2
Me
O2, AcOH
60C, 68%
OMe
OOH
O
Me
Me
80C, 2h
59%
Me
SiEt3
O
same
Me
MeOH, RT
83%
O
OMe
Me
Me
Me
61%
Me
Me
SiEt3
same
Me
39%
Me
Me
SiEt3
O
JACS (107) 2980
Fe(OAc)2
76%
H
H
O
Me
O
H
O
O
Cyclopropyldiphenylsulfonium Tetrafluoroborate
Fe(OAc)2 O
67%
O
Me
Me
KOH, DMSO
96%
O
O
O
Me
Me
96%
Tol
O
Me
Me
BF4
Tol
Me
H
O
HBF4
OH
LDA
Me
O
O
SPh2
O
O
BF4
O
Me
Cu(OAc)2
Fe(OAc)2
Me
O
O3, MeOH;
Cu(OAc)2
Me
1. O3, MeOH Me
2. Cu(OAc)2
Me
1 mol% Ru(cod)(cot)
Et3SiH
Me
5 eq
Cu(OAc)2
Fe(OAc)2
OH
O
O
(1,5-Cyclooctadiene)(1,3,5-cyclooctatriene)ruthenium
OMe
O
MeO
Me
Tet Lett (34) 567
OMe
89%
2. HCl, MeOH
60%
JACS (91) 3676
AcOH, 60C
74%
Copper(II) Acetate–Iron(II) Sulfate
MeO
Me
Me
16-18C
96%
tBuOOH
Cu(OAc)2
1. N3CN, LiClO4
MeOH
Me
NCN
N3CN
O3
OPh
OPh
PhO
92%
Cyanogen Azide
Copper(II) Acetate
10 eq
OPh
MeCN, RT
C4H9
O
HO
Tetrahedron (47) 297
Me
Will Gutekunst
Hexane, RT
ca quant
SPh2
CO2Me
KOH, DMSO
83%
OH
LiN
CO2Me
Tol
O
Me
Copper(I) Iodide–Triethylphosphine–Lithium Naphthalenide
O
Br
OH
OH
CuI, Bu3P
LiNp
Cyclopropyltriphenylphosphonium Bromide
O
Br
N
N
68%
Toluene (45%)
THF (56%)
1:0
1:6
Tetrahedron (45) 443
O
O
CO2Et
O
OH
PPh3
CO2Et
R1
R2
Br
PPh3
NaH
88-95%
EtO2C
R1
R2
CO2Et
JACS (96) 1607
EROS: Vol I and II
Baran Group Meeting
1,4-Diazabicyclo[2.2.2]octane
(Diacetoxyiodo)benzene
2 eq PIDA
4 eq TMSN3
Ph
Me
Ph
O
CN
Me
2 eq PIDA
4 eq TMSN3
Me
Me
DCM, 61%
DCM, 65%
H
HN N
PIDA
R
MeOH, -23C
60%
O
R
MeO2C
O
Me
Me
PIDA
Me
Ph
CN
R
R = Me, CO2Me, CH2CO2Me, Ph, etc
H
R
Br
O
O
DABCO
NaNH2
O
R = Me, Et, CH2CO2Me, Bn
MeO
NH2
PhH, reflux
76%
OMe
MeO
Synthesis (1975) 395
Cr(II)en
10% aq DMF
Cr(II)en
10% aq DMF
I
RT, 92%
H
RT, quant
I
O
Cl
H
O
Tetrahedron (24) 3503
C15H31
2h, 90%
(CH2)n Me
Me
Me
H
(CH2)n+1
R
O
H
O
OH
H
H
Me
H
O
OH
Me
H
O
CH2N2
OH OH
MeMe
R
Me
O
10 mol%
O
NC
OMe
CN
H
Me
H
OH
H
O
OMe OH
1. CH2N2
CN
2. HClO4
Te
MeO
OMe
O
O
NC
O
O
JACS (110) 2506
Tol, reflux
96%
Te
MeO
OMe
Me
OH
H
O Me
H
H
Me
Te
H
H
MeO
R
H
Me
HBF4
OH
Me
O
CH2N2
MeMe
Me
Me C8H17
H
H
HO
Dianisyl Telluroxide
MeO
Me
Diazomethane
cis:trans 2:3
5 min
71-76%
R = butyl, pentyl, octyl
n = 2,3
Me
Me C8H17
reflux in DAE
Li, DAE
10-15C
PhH/Hexane
90%
Me
NH2
LiHN
C15H31
O
Me
Greatly increases the ability of Cr(II) to reduce alkyl halides, aryl halide and epoxides.
O
S
DABCO
DMSO, RT
Cl
S
no benzyne
HO
I
O
"Haller Bauer Cleavage"
1,2-Diaminoethane
R
Ph
80C, 24h
92%
Tetrahedron (45) 1605
O
Ph
Et
DABCO forms stable, crystalline complex with organometallic complexes with Li, Zn and Mg
organometallics
Also promotes lithiation of toluene, benzene, etc.
H
MeO2C
MeOH, -23C
57-66%
O
H
1. DABCO, BuLi
PhSMe
2. NaI, MeI, DMF
Ph
Et
Tetrahedron (26) 2945
H
HN N
Will Gutekunst
OMe
Tet Lett (22) 5251
Me CO2Cl
Me
O
J. Chem. Soc. Perkin 1
(1981) 1203
EROS: Vol I and II
Baran Group Meeting
Diazomethane (cont.)
Me
Me
Me
Et3N
CH2N2
Me
O
O
SO2Cl
TMS O
CH2N2
OMe
TMS
O
OMe
Journal of Organometallic Chemistry (52) C7
Will Gutekunst