gave (13) in 70–90% yields and >95% purity. Complexes of Cr(II) with L = EDTA, NTA were similarly efficient with chloride (2) in furnishing glucal 13, while with L = IDA, GLY, MAL hydrolysis of 2 could not be suppressed. Under the same conditions [CrII(EDTA)]2− also efficiently gave the corresponding glycals 14–19 from and bromide (5), per-O-acetylated α-d-galactopyranosyl chloride (6) and bromide (7)
的反应
溴化物(3)用
铬(II)L-络合物(L =
EDTA,
NTA,
IDA,GLY,MAL)在中性(5 95纯度%。Cr(II)与L =
EDTA,
NTA的配合物与
氯化物(2)在提供
葡聚糖13方面同样有效,而L =
IDA,GLY则无法抑制2的MAL
水解。在相同条件下[CR II(
EDTA)] 2-也有效地得到相应的烯糖14-19从和
溴化物(5),per- Ô -acetylatedα-d
吡喃半
乳糖基
氯化物(6)和
溴化物(7),α-d-
吡喃
吡喃糖基
氯(8),α-d-
吡喃
吡喃糖基
氯(9)和
溴化物(10),β-d-阿拉伯
吡喃糖基
溴化物(11)和α-1-
鼠李糖基
吡喃糖基
氯化物(12)。