F. Bitterer et al., WATER-SOLUBLE PHOSPHANES .4. TERTIARY ALK YLPHOSPHANES WITH AMMONIUM GROUPS IN THE SIDE-CHAINS - AMPHIPHILES WITH BASIC P-ATOMS, Chemische Berichte, 128(3), 1995, pp. 275-279
By stepwise aminoalkylation of PH3 with Me(2)N-(CH2)(2)-Cl in the supe
rbasic medium DMSO/KOH the secondary phosphane [Me(2)N-(CH2)(2)]2PH (2
) is obtained in good yields. Metallation of 2 with n-BuLi and subsequ
ent reaction with Me(2)N-(CH2)(2)-Cl affords the basic tertiary phosph
ane [Me(2)N-(CH2)(2)]P-3 (3), which on protonation with Ph(3)P . HBr i
n CH2Cl2 gives {[HNMe(2) - (CH2)(2)]P-3}(3+) 3 Br- (4a) with an extrem
ely high solubility in water. By oxidation of 3 with H2O2 and N-quater
nisation with Me(3)O(+) BF4- the cationic phosphane oxide {[Me(3)N- (C
H2)(2)]P-3=O}(3+) 3 BF4- (5a) is formed, which could, however, not be
reduced with SiHCl3 or Si2Cl6/NEt(3) to the corresponding tricationic
phosphane. Tertiary cationic phosphanes of type [RMe(2)N-(CH2)(2)-P(Oc
t)(2)](+)X(-) (8a, 8b, R = Me, C8H17; X = Br, I) are accessible by fre
e radical addition of 1-octene to 7b and 7d, Addition of formaldehyde
to 7a gives the hydroxymethyl phosphane 10a. By methylation of [RMe(2)
N-(CH2)(2)-PH2]I-+(-) (7d and 7e, R = CnH2n+1, n = 8, 12) with MeI und
er controlled condition and subsequent deprotonation of the phosphoniu
m salts 12b and 12e the cationic tertiary phosphanes 13a and 13b with
long alkyl, side chains may be obtained in good yields.