2 Homometallic Alkoxides

48 Alkoxo and Aryloxo Derivatives of Metals
2.10.3 From Metal–Carbon and Metal–Nitrogen Bond Cleavage Reactions (J-3)
[Me3Si⊳2N]2M⊲CH2SiMe2NSiMe3⊳
C4Pr i OHCpy
3⊲Me3Si⊳2NH
CPr i OH
3HN⊲SiMe3⊳2
! 1
4 M4⊲OPri⊳16⊲py⊳2 M D Th165 ! [M⊲OPr i ⊳4]n
M D Th 165
(2.143)
(2.144)
C4HOCHPr i 2 ! 1
2 M2⊲OCHPr i 2 ⊳8 C 3⊲Me3Si⊳2NH
M D Th 407 (2.145)
C4HOCHEt2Cpy
! 1
2 [M2⊲OCHEt2⊳8]⊲py⊳2
M D Th165 (2.146)
>4Bu t OH/toluene
! 1
2 [M2⊲OBu t ⊳8⊳]⊲HOBu t ⊳ C 3⊲Me3Si⊳2NH
M D Th 406 (2.147)
>4.5Bu t OH
3⊲Me3Si⊳2NH
2.10.4 From Metal–Hydrogen Bond Cleavage Reactions (J-4)
! 1
2 [M2⊲OBut⊳8]⊲HOBut⊳ (2.148)
M D U330 The hydridic metal hydrides react with alcohols to yield hydride-alkoxides or binary
alkoxides depending on the amounts of alcohols used.
Tetrahydrofuran soluble magnesium dialkoxides Mg⊲OR⊳2 (where R D CPh3 or
CMePh2) have been prepared 408 by the reactions of magnesium hydride or dimethyl
magnesium with the corresponding alcohols:
MgH2 (or MgMe 2 ⊳ C 2ROH ! Mg⊲OR⊳2 C H2 (or 2CH 4⊳ ⊲2.149⊳
The hydrocarbon soluble alkoxides of even the heavier alkaline earth metals (Ba)
are accessible 47 according to Eq. (2.150):
BaH2 C 2ROH ! Ba⊲OR⊳2 C 2H2 " ⊲2.150⊳
where R D CH⊲CF3⊳2 or C⊲CF3⊳3.
In view of the importance of zinc hydride derivatives as catalysts for methanol
production, 409,410 a number of alkoxozinc hydrides have been prepared by the reactions
of ZnH2 with a variety of alcohols:
2ZnH2 C 2ROH ! 2HZn⊲OR⊳ C H2 ⊲2.151⊳
where R D c-C6H11, 411 CH2CH2NMe2, 412 and Bu t . 413
Aluminium hydride undergoes stepwise substitution 414 by alcohols (Eq. 2.152):
AlH3 C xROH ! Al⊲OR⊳x H3 x C x/2H2 ⊲2.152⊳