Ser
ies of germatrane compounds w
ith OH funct
ional
ity and Ge鈰疦 transannular bond
ing,
i.e. 1-germatranol (
I), 1,1-quas
igermatranol (
II) and 1,1,1-hypogermatranol (
III) w
ith general formula (HO)
4聽鈭捖?em>nGe(OCH
2CH
2)
nNR
3聽鈭捖?em>n (R聽=聽H, Me;
n聽=聽1-3) are synthet
ized and the
ir sol
id state IR spectra are recorded. Equ
il
ibr
ium structures and v
ibrat
ional spectra of monomer
ic and centrosymmetr
ic d
imer
ic spec
ies of these compounds are pred
icted by the DFT B3LYP/aug-cc-pVDZ method. The ass
ignment of the v
ibrat
ional spectra of
I-
III was carr
ied out based on theoret
ical IR spectra scaled w
ith factors obta
ined earl
ier for halogermatranes to take account of the substant
ial and systemat
ic d
iscrepancy between Ge鈰疦
interatom
ic d
istance of the gas phase and theoret
ical pred
ict
ions on the one hand and X-ray sol
id state data on the other. D
imer
ic models prov
ide a good agreement between exper
imental and pred
icted frequenc
ies,
includ
ing GeOH bend
ing modes, of
I, crystall
ine state of wh
ich
is formed by d
imers, and sl
ightly worse for
II,
in wh
ich some weaker O-H鈰疧 and N-H鈰疧 hydrogen bonds are not cons
idered
in the d
imer
ic model.
However, this model for III is poor since it does not take into account hydrogen bonding of 鈥渇ree鈥?OH and NH2 groups. Despite the steady decrease of the Ge鈰疦 interatomic distance, corresponding frequencies demonstrate the substantial increase on going from I to II and practically no increase from II to III.