TY - JOUR
T1 - A new route to sila- and phosphaheterocycles
T2 - Nucleophilic aminomethylation
AU - Karsch, Hans H.
AU - Schreiber, Kai A.
AU - Herker, Martin
PY - 1997
Y1 - 1997
N2 - The aminals tetramethylmethylenediamine (TMMDA) la, dicyclohexyldimethylmethylenediamine (CMMDA) Ib, and diisopropyldimethylmethylenediamine (IMMDA) le are doubly metalated by Liffiu to give LiCH2N(R)CH2N(R)CH2Li [2a: R = Me, 2b: R = Cy (Cy = cyclohexyl), 2c: R = iPr], which precipitate out of pentane as highly pyrophoric substances. Deuteration confirms N-methyl metalation exclusively. A series of aminomethylation reactions were performed by means of the doubly lithiated aminals 2a-c. The reactions of 2a-c with monochlorosilanes yield the silylated species R′3SiCH2N(R)CH2N(R)CH 2SiR′3 (3a: R′= Me, R = Me; 3b: R′ = Me, R = Cy; 3c: R′= Me, R = iPr; 4: R′= Ph, R = Me, see Scheme 2). The use of dichlorosilanes lead to six-membered heterocycles 6a-6d. 6a is transferred into a mono quartemary ammonium salt 7 by methylation with Mel. The spirocycle 8 is obtained from SiCl4 and two equivalents of 2a. Similarly, several substituted l,3-diaza-5-phosphacyclohexanes 9a-e (R1 = Me, Ph, NPh2, NCy2, see Scheme 3) are synthesized by the reaction of dichlorophosphanes R1PCl2 with 2a and 2b, respectively. Oxidation of 9d with sulfur yields 12 a, which is characterized by X-ray structure determination.
AB - The aminals tetramethylmethylenediamine (TMMDA) la, dicyclohexyldimethylmethylenediamine (CMMDA) Ib, and diisopropyldimethylmethylenediamine (IMMDA) le are doubly metalated by Liffiu to give LiCH2N(R)CH2N(R)CH2Li [2a: R = Me, 2b: R = Cy (Cy = cyclohexyl), 2c: R = iPr], which precipitate out of pentane as highly pyrophoric substances. Deuteration confirms N-methyl metalation exclusively. A series of aminomethylation reactions were performed by means of the doubly lithiated aminals 2a-c. The reactions of 2a-c with monochlorosilanes yield the silylated species R′3SiCH2N(R)CH2N(R)CH 2SiR′3 (3a: R′= Me, R = Me; 3b: R′ = Me, R = Cy; 3c: R′= Me, R = iPr; 4: R′= Ph, R = Me, see Scheme 2). The use of dichlorosilanes lead to six-membered heterocycles 6a-6d. 6a is transferred into a mono quartemary ammonium salt 7 by methylation with Mel. The spirocycle 8 is obtained from SiCl4 and two equivalents of 2a. Similarly, several substituted l,3-diaza-5-phosphacyclohexanes 9a-e (R1 = Me, Ph, NPh2, NCy2, see Scheme 3) are synthesized by the reaction of dichlorophosphanes R1PCl2 with 2a and 2b, respectively. Oxidation of 9d with sulfur yields 12 a, which is characterized by X-ray structure determination.
KW - Aminomethylation
KW - Diazaphosphaheterocycles
KW - Diazasilaheterocycles
KW - Lithiation
KW - Nitrogen heterocycles
UR - http://www.scopus.com/inward/record.url?scp=33745373939&partnerID=8YFLogxK
U2 - 10.1002/cber.19971301212
DO - 10.1002/cber.19971301212
M3 - Article
AN - SCOPUS:33745373939
SN - 0009-2940
VL - 130
SP - 1777
EP - 1785
JO - Chemische Berichte
JF - Chemische Berichte
IS - 12
ER -