Biomedical Engineering Reference
In-Depth Information
SCHEME 2.1
Reagents and conditions: (a) HC_C-SiMe3, cat. Pd(PPh3)4, cat. CuI, Et3N, THF,
reflux; (b) LiAlH4, ether; (c) Bu4NF, THF, overall 83% (three steps); (d) MsCl, Et3N, CH2Cl2; (e)
(1R,2S)-ephedrine_HCl, K2CO3 CH3CN, reflux, overall 76% (two steps)
214
.
Copyright permission
from reference 214.
SCHEME 2.2
Reagents and conditions: (a)
4
(2 mol equiv.), cat. Pd(PPh3)4, cat. CuI, Et3N, THF,
reflux, 49%; (b)
4
(5 mol equiv.), cat. Pd(PPh3)4, cat. CuI, Et3N, DMF, 66%; (c) HC_C-SiMe3, cat.
Pd(PPh3)4, cat. CuI, Et3N, DMF, 69%; (d) Bu4NF, THF, 83%; (e)
7
(5 mol equiv.), cat. Pd(PPh3)4,
cat. CuI, Et3N, DMF, 88% based on
5
214
.
Copyright permission from reference 214.
(6)
On the other hand, coupling reaction of
7
with
5
result in
1b
(G2) contain-
ing six catalytic sites giving 88% yield.
Using this process developed by Sato's group, chiral dendrimers
1a
(G1) and
1b
(G2) with rigid hydrocarbon backbones are useful catalysts for the enantiose-
lective addition of dialkylzincs. Application of these chiral dendrimers to other
asymmetric syntheses is currently being studied at the same laboratory.
2.6 CHARACTERIZATION OF NM
s
215
The novel properties of materials with nanometer dimensions (and not associ-
ated chemical changes) require surface chemical characterization of paramount
necessity to establish topographical properties that are important for biomedi-
cal and biological applications.
215
Thus, it is inevitable to include some tech-
niques that have been used for NM surface chemical characterization and the
determination of protein biomolecule interactions aside from those already dis-
cussed in the previous sections of this chapter. Techniques that are discussed
here are attenuated total reflectance Fourier transform infrared (ATR-FTIR)
