Categories: C-C Bond Formation > Nitrogen-containing molecules > Synthesis of amines >
Benzylamines
| Related: |
 |
 |
Name Reactions
Recent Literature
A highly efficient Zn-catalyzed alkylation of ketones and aldimines with
Grignard reagents via trialkylzinc(II) ate complexes minimizes
problems with the use of only Grignard reagents, which leads to reduction
and aldol side products, and the yield of desired alkylation products could
be improved.
M. Hatano, S. Suzuki, K. Ishihara, J. Am. Chem. Soc., 2006,
128, 9998-9999.
N-Benzyldiphenylphosphinamides are deprotonated at the NCα position
diastereospecifically upon treatment with t-BuLi in diethyl ether at low
temperature. Reaction of the anions with various electrophiles and subsequent cleavage of the P-N linkage affords 1,2-amino alcohols and α-, β-, and γ-amino
acids.
P. O. Burgos, I. Fernández, M. J. Iglesias, S. García-Granda, F. L. Ortiz, Org. Lett., 2008,
10, 537-540.
A highly efficient three-component coupling reaction between thioformamides and
organolithium and Grignard reagents was developed. The generality of the process
has been demonstrated by using various combinations of reactants and reagents.
T. Murai, F. Asai, J. Am. Chem. Soc., 2007,
129, 780-781.
Sequential addition reactions of Grignard reagents to thioformamides give
tertiary amines in an efficient manner. The addition of different Grignard
reagents can be accomplished by using one equivalent of arylmagnesium reagent in
the first step followed by alkyl, alkenyl, aryl, or alkynyl reagents to afford
the corresponding amines in good to high yields.
T. Murai, K. Ui, Narengerile, J. Org. Chem., 2009,
74, 5703-5706.
A mild, versatile, copper-catalyzed three-component coupling of organoindium
reagents with imines and acid chlorides provides α-substituted amides or
N-protected amines in a single step with the sole byproduct being indium
trichloride.
D. A. Black, B. A. Arndtsen, Org. Lett.,
2006,
8, 1991-1993.
A rhodium complex coordinated with the chiral diene Ph-bod* catalyzed the
asymmetric addition of dimethylzinc to
N-tosylarylimines to give high yields of chiral 1-aryl-1-ethylamines
with high enantioselectivity.
T. Nishimura, Y. Yasuhara, T. Hayashi, Org. Lett.,
2006,
8, 979-981.
Various
N-toluenesulfonylimines were
successfully ethylated with diethylzinc in the presence of copper(II) ditriflate
and a chiral amidophosphine ligand in toluene to give the corresponding N-toluenesulfonylamides in good yields and high enantioselectivity.
T. Soeta, K. Nagai, H. Fujihara, M. Kuriyama, K. Tomioka, J. Org. Chem.,
2003, 59, 9655-9659.
N-formyl-α-(p-tolysulfonyl)benzylamines are readily available
starting materials which upon deprotonation eliminate the sulfinate group to
give an acyl imine. The acyl imines further react with alkylzinc reagents in
the presence of catalytic amounts of chiral [2.2]paracyclophane-based N,O-ligands
to alkylated N-(1-phenylpropyl)formamides with excellent yields and
enantioselectivities.
S. Dahmen, S. Braese, J. Am. Chem. Soc., 2002,
124, 5940-5941.
The use of ZnCl2, Me3SiCH2MgCl, and LiCl
effectively minimizes problematic side reactions in the 1,2-addition of strongly
basic alkyl and aryl Grignard reagents to ketones. Aldimines give secondary
amines in high yield. The simplicity of this reliable ZnCl2•Me3SiCH2MgCl•LiCl
system might be attractive for industrial as well as academic applications.
M. Hatano, O. Ito, S. Suzuki, K. Ishihara, J. Org. Chem., 2010,
75, 5008-5016.
LnCl3•2 LiCl (Ln = La, Ce, Nd) are superior promoter
for the addition of various organometallic reagents to ketones. They also
catalyze efficiently the addition of organomagnesium compounds to imines.
A. Krasovskiy, F. Kopp, P. Knochel, Angew. Chem. Int. Ed., 2006,
45, 497-500.
Under selected conditions, the Zr-catalyzed reaction of EtMgCl with imines
produces C,N-dimagnesiated compounds, which can be further trapped with
electrophiles. The overall transformation provides a new route to
bifunctional or cyclic nitrogen-containing compounds such as
1-azaspirocyclic γ-lactams, pyrrolidines and azetidines.
V. Gandon, P. Bertus, J. Szymoniak, Synthesis,
2002, 1115-1120.
Allylic N-sulfonylamines are synthesized in high yields and with high
regioselectivities by reaction of
N-sulfonylaziridines with excess dimethylsulfonium methylide.
D. M. Hodgson, M. J. Fleming, S. J. Stanway, Org. Lett., 2005,
7, 3295-3298.
Trialkylalanes undergo addition to imines in the presence of a catalytic
amount of dichlorodicyclopentadienylzirconium(IV). The reaction tolerates
the presence of various functional groups. A possible reaction pathway is
discussed.
C. Denhez, J.-L. Vasse, J. Szymoniak, Synthesis, 2005,
2075-2079.
1-Aryl-substituted primary cyclopropylamines are conveniently prepared from
aromatic nitriles and diethylzinc in good yields.
S. Wiedemann, D. Frank, H. Winsel, A. de Meijere, Org. Lett.,
2003, 5, 753-755.
The reaction of various aromatic nitriles and conjugated alkenenitriles with 1.1
equiv of Ti(OiPr)4 and 2.2 equiv of EtMgBr followed by addition of a
Lewis acid gave 1-arylcyclopropylamines and 1-alkenylcyclopropylamines in good
yields.
P. Bertus, J. Szymoniak, J. Org. Chem., 2003,
68, 7133-7136.
The combination of ytterbium trifluoromethanesulfonate [Yb(OTf)3]
and chlorotrimethylsilane catalyzed the imino ene reaction of
N-tosyl aldimine with α-methylstyrene to give a homoallylamine in
excellent yield. The addition of a catalytic amount of silane (TMSCl or
TMS(OTf)) increased the yield dramatically.
M. Yamanaka, A. Nishida, M. Nakagawa, Org. Lett., 2000,
2, 159-161.
A nucleophilic trifluoromethylation reaction of carbonyl
compounds with Ruppert’s reagent, Me3SiCF3, was efficiently
promoted by a P(t-Bu)3-DMF system. Imines were also converted to the desired
α-trifluoromethyl amines under similar reaction conditions.
S. Mizuta, N. Shibata, T. Sato, H. Fujimoto, S. Nakamura, T. Toru, Synlett,
2006, 267-270.
Alkoxide-induced nucleophilic pentafluoroethylation and trifluoromethylation
of aldehydes, ketones, and imines using pentafluoroethyl phenyl sulfone and
trifluoromethyl phenyl sulfone, respectively, have been successfully achieved.
G. K. S. Prakash, Y. Wang, R. Mogi, J. Hu, T. Mathew, G. A. Olah, Org. Lett., 2010,
12, 2932-2935.
β-Functionalized sulfonamides were produced in good yields by the
regioselective ring opening of N-tosylaziridines with
trimethylsilylated nucleophiles, catalyzed by N,N,N',N'-tetramethylethylenediamine
(TMEDA).
S. Minakata, Y. Okada, Y. Oderaotoshi, M. Komatsu, Org. Lett.,
2005,
7, 3509-3512.