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A Simple Three-Component Reaction for the Preparation of Silylated Primary Amines
@
Tetrahedron
Pergamon
Later.,
Vol. 38, No. 46, 431997
pp. 8071-8072,
1997
ElsevierScienceLtd All rightsreserved.Printedin GreatBritain 0040-4039/97 $17.00+ O.co
PII: SOO4O-4O39(97)1O1 10-1
A Simple Three-Component Reaction for the Preparation of SilylatedPrimary Amines Mohammad R Saidi *8,Mohammad M. Mojtahedi 8,Mohammad Bolourtchian ~
‘ Departmentof Chemistry,SharifUniversityof TechnologyP. O. Box 11356-9516, Teheran,and bChemistry&ChemicalEngineeringResearchCenterof Irart,P. 0. Box 14335-186,Teheran,I. R. of Iran
Abstract : In the presenceof lithiumperchloratein diethylether, three-componentreactionbetween aldehydes, hexarnethyh-lisilazane,and silylated nucleophiles proceeded smoothly to afford trirnethylsilylatedprimaryarnirresin goodyields, @ 1997Elsevier Science Ltd.
Recently,we reported the lithiumperchloratemediatedone pot three-componentaminosilylationof aldehydes,1, with (trimethylsilyl)dialkylamines,2, and organosiliconnucleophiles,for the preparationof dialkyl-y-trimethylsilyl-fLynamines, 4, and dialkyl-fWimethy lsilyl-amines, RICHO
+
RlCH=fi2 R’ H-% ~ 7 3 ‘OSiMe3 OSiMe3 R1CHC=CSi(CH3)3 LiC ❑CSi(CH3)3 ~ NR2 4 rt BrMgCH2Si(CH3)3 ~ R1CHCH2Si(CH3)3
Me3SjNR2
1
5, Scheme 1’-5
‘~~~’l >
2
3+ 3+
Scheme 1
I@5
Aldehyde,1, reacts with sodiumor lithium hexamethyldisilazane in the presenceof 5 M solutionof lithium perchlorate in diethyl ether, at r.t. to produce imine, 6, in situ, in about 30 min. Reaction of lithium (trimethylsilyl)acetylide or trimethylsilylmethylmagnesium chloridein diethylether with 6 at r.t, affordedthe correspondingy-trimethylsilyl-~-ynamines, 7, and ~-trimethykilyl-amines, 8, respectively,Scheme 2. RCHO
+
(Me3Si)2NLi
‘:~~j4
R~H-N(SiMe3)2~’
,
0-
1
6+
LiC~CSi(CH3)3
6+
BrMgCH2Si(CH3)3~
A
Scheme 2
[RCH=NSiMe3] 6 R~HC=CSi(CH3)3 7 (a-e) NH2 R~H CH2Si(CH3)3 *2
8 (a-e)
The structureand the yieldsof the silylatedproductsare shownin Table 1. Whenthe reactionwas carried out withoutusing 5 M LiC104diethylethersolution,products7 and 8 were producedinverylow yields. Experimental
LiC104(Fluka)was driedat 160‘C and 10-1Torr for 48 h. Caution: Althoughwe did not haveanyaccidentinusingLiC104,the authorsadviseto dry lithiumperchlorate
in hoodusingsuitableIab-sheild. 8071
8072
General Pracedurefor the Preparation of ytrimethylsi!yl-~ynamines or @-imethylsilyl-amines: Hexamethyldisilazane (3.3 mmol,0.54g)was placedin two-neckedflaskfittedwitha condenser,and a stirring bar under argo~ and 3.5 mmolof sodiumhydride(60-65%,after washingwith lightpet. ether) or 3.4 mmol of methyllithiumin dry diethylether was add~ andthe mixture was stirred for for about 5 min.Then3 d, solutionof 5 M lithiumperchloratein diethylether and 2 mmolof aldehydewere added via syringe. After stirringfor 30 min.,lithium(trimethylsilyl)acetylide or trimethylsilylmethylmagnesium chloride(4 mmol)was added, and the mixturewas stirredfor additional30 min. Water (10 rnL)was added, and the product was extracted with ether ( 2x 10).The organiclayerwas separatedand extractedwith cold 0.5 M HC1solution. Neutralizationwith 2.0 M solutionof KOH, gave the desired product. Further purificationwas done by preparativegas chromatographyif needed. All products describedhad structures in accordancewith their spectroscopicdata. Table 1 Entqi
Aldehyde
1
C6H5CH0
22
33
Prodwr c6H5~H=cs~:3 NH2
C6H5CH=CHCH0 S
CHO
\l (-)’ CHO
4* .45 t6 7
Acknowledgment
0’ 0’ ‘1 <
‘1 MeO ‘
CHO
C6H5CH0
s
CHO
8[
wII
9(
:1 MeO00’
C6H5CH=CH C~CSiMe3 F ~2 7b s HCECSiMe3 (--y ‘ f NH’2 7C CHCSCSiMe3 , : I ~2 7d a CHC~CSiMe3 :1 ~2 7e MeO
0’
c6H5~HcH2siMe3 M2 8a
C6H5CH=CHCH0
CHO
Yield
0/0
C6H5CH=CHHCH2SiMe3 L .. 8b s HCH@Me3 fyi \ I ~2 8C ~HCH2SiMe3 :1 ‘Z Se MeOD
70 75 72 68 73 75
69 60 60
We wouldliketo acknowledge“ Volkswagen-Stiftung, FederalRepublicof Oermany“
for financialsupport to purchaselaboratoryequipments. We also would like to thank ResearchCouncilof SharifUniversityof Technologyfor its partialfinancialsuportof thiswork. References 1. KleimnanE. F., in Comprehensive Organic Synthesis (Eds;B. Trost, I. Fleming),PergamonPress,Oxford,
1991,Vet. 2, pp 893-951. 2.Wang,J.; Zhang,Y.; 13ao,W., S’. Comm.,1996,26,2473-2477. 3. Henry,Jr.,K.J.; Grieco,P.~ Chem. Commtor., 1993, 510-512; Orieco, P.A.;Moher,E.D. Teirahe&on Left., 1993,34, 5567-5570; 4. Saidi,M. R.; Heydari,A.;Ipaktschi,J., Chem. Eer., 1994,127,1761-1763. 5. Saidi,M. R.; Mojtahedi,M. M; Bolourtchian,M., Iranian J. Science & Tech., Trans.A, 1995, 19,201204; Saidi,M. R.; Mojtahedi,M. M; Bolourtchian,M., J. Sciences,I.R. Iran, 1995,3, 163-165.
(Received in UK 30 May 1997;accepted 12 September 1997)
Tetrahedron
Pergamon
Later.,
Vol. 38, No. 46, 431997
pp. 8071-8072,
1997
ElsevierScienceLtd All rightsreserved.Printedin GreatBritain 0040-4039/97 $17.00+ O.co
PII: SOO4O-4O39(97)1O1 10-1
A Simple Three-Component Reaction for the Preparation of SilylatedPrimary Amines Mohammad R Saidi *8,Mohammad M. Mojtahedi 8,Mohammad Bolourtchian ~
‘ Departmentof Chemistry,SharifUniversityof TechnologyP. O. Box 11356-9516, Teheran,and bChemistry&ChemicalEngineeringResearchCenterof Irart,P. 0. Box 14335-186,Teheran,I. R. of Iran
Abstract : In the presenceof lithiumperchloratein diethylether, three-componentreactionbetween aldehydes, hexarnethyh-lisilazane,and silylated nucleophiles proceeded smoothly to afford trirnethylsilylatedprimaryarnirresin goodyields, @ 1997Elsevier Science Ltd.
Recently,we reported the lithiumperchloratemediatedone pot three-componentaminosilylationof aldehydes,1, with (trimethylsilyl)dialkylamines,2, and organosiliconnucleophiles,for the preparationof dialkyl-y-trimethylsilyl-fLynamines, 4, and dialkyl-fWimethy lsilyl-amines, RICHO
+
RlCH=fi2 R’ H-% ~ 7 3 ‘OSiMe3 OSiMe3 R1CHC=CSi(CH3)3 LiC ❑CSi(CH3)3 ~ NR2 4 rt BrMgCH2Si(CH3)3 ~ R1CHCH2Si(CH3)3
Me3SjNR2
1
5, Scheme 1’-5
‘~~~’l >
2
3+ 3+
Scheme 1
I@5
Aldehyde,1, reacts with sodiumor lithium hexamethyldisilazane in the presenceof 5 M solutionof lithium perchlorate in diethyl ether, at r.t. to produce imine, 6, in situ, in about 30 min. Reaction of lithium (trimethylsilyl)acetylide or trimethylsilylmethylmagnesium chloridein diethylether with 6 at r.t, affordedthe correspondingy-trimethylsilyl-~-ynamines, 7, and ~-trimethykilyl-amines, 8, respectively,Scheme 2. RCHO
+
(Me3Si)2NLi
‘:~~j4
R~H-N(SiMe3)2~’
,
0-
1
6+
LiC~CSi(CH3)3
6+
BrMgCH2Si(CH3)3~
A
Scheme 2
[RCH=NSiMe3] 6 R~HC=CSi(CH3)3 7 (a-e) NH2 R~H CH2Si(CH3)3 *2
8 (a-e)
The structureand the yieldsof the silylatedproductsare shownin Table 1. Whenthe reactionwas carried out withoutusing 5 M LiC104diethylethersolution,products7 and 8 were producedinverylow yields. Experimental
LiC104(Fluka)was driedat 160‘C and 10-1Torr for 48 h. Caution: Althoughwe did not haveanyaccidentinusingLiC104,the authorsadviseto dry lithiumperchlorate
in hoodusingsuitableIab-sheild. 8071
8072
General Pracedurefor the Preparation of ytrimethylsi!yl-~ynamines or @-imethylsilyl-amines: Hexamethyldisilazane (3.3 mmol,0.54g)was placedin two-neckedflaskfittedwitha condenser,and a stirring bar under argo~ and 3.5 mmolof sodiumhydride(60-65%,after washingwith lightpet. ether) or 3.4 mmol of methyllithiumin dry diethylether was add~ andthe mixture was stirred for for about 5 min.Then3 d, solutionof 5 M lithiumperchloratein diethylether and 2 mmolof aldehydewere added via syringe. After stirringfor 30 min.,lithium(trimethylsilyl)acetylide or trimethylsilylmethylmagnesium chloride(4 mmol)was added, and the mixturewas stirredfor additional30 min. Water (10 rnL)was added, and the product was extracted with ether ( 2x 10).The organiclayerwas separatedand extractedwith cold 0.5 M HC1solution. Neutralizationwith 2.0 M solutionof KOH, gave the desired product. Further purificationwas done by preparativegas chromatographyif needed. All products describedhad structures in accordancewith their spectroscopicdata. Table 1 Entqi
Aldehyde
1
C6H5CH0
22
33
Prodwr c6H5~H=cs~:3 NH2
C6H5CH=CHCH0 S
CHO
\l (-)’ CHO
4* .45 t6 7
Acknowledgment
0’ 0’ ‘1 <
‘1 MeO ‘
CHO
C6H5CH0
s
CHO
8[
wII
9(
:1 MeO00’
C6H5CH=CH C~CSiMe3 F ~2 7b s HCECSiMe3 (--y ‘ f NH’2 7C CHCSCSiMe3 , : I ~2 7d a CHC~CSiMe3 :1 ~2 7e MeO
0’
c6H5~HcH2siMe3 M2 8a
C6H5CH=CHCH0
CHO
Yield
0/0
C6H5CH=CHHCH2SiMe3 L .. 8b s HCH@Me3 fyi \ I ~2 8C ~HCH2SiMe3 :1 ‘Z Se MeOD
70 75 72 68 73 75
69 60 60
We wouldliketo acknowledge“ Volkswagen-Stiftung, FederalRepublicof Oermany“
for financialsupport to purchaselaboratoryequipments. We also would like to thank ResearchCouncilof SharifUniversityof Technologyfor its partialfinancialsuportof thiswork. References 1. KleimnanE. F., in Comprehensive Organic Synthesis (Eds;B. Trost, I. Fleming),PergamonPress,Oxford,
1991,Vet. 2, pp 893-951. 2.Wang,J.; Zhang,Y.; 13ao,W., S’. Comm.,1996,26,2473-2477. 3. Henry,Jr.,K.J.; Grieco,P.~ Chem. Commtor., 1993, 510-512; Orieco, P.A.;Moher,E.D. Teirahe&on Left., 1993,34, 5567-5570; 4. Saidi,M. R.; Heydari,A.;Ipaktschi,J., Chem. Eer., 1994,127,1761-1763. 5. Saidi,M. R.; Mojtahedi,M. M; Bolourtchian,M., Iranian J. Science & Tech., Trans.A, 1995, 19,201204; Saidi,M. R.; Mojtahedi,M. M; Bolourtchian,M., J. Sciences,I.R. Iran, 1995,3, 163-165.
(Received in UK 30 May 1997;accepted 12 September 1997)