中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | 5-Benzyloxy-3-bromo-1,4-dimethoxynaphthalene | 222728-58-7 | C19H17BrO3 | 373.246 |
—— | 5-Benzyloxy-3-bromo-4-hydroxy-1-methoxynaphthalene | 367253-68-7 | C18H15BrO3 | 359.219 |
中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
2-溴-1,4,8-三甲氧基萘 | 2-bromo-1,4,8-trimethoxynaphthalene | 95375-27-2 | C13H13BrO3 | 297.148 |
—— | 1,4,5-trimethoxynaphthalene | 64636-39-1 | C13H14O3 | 218.252 |
In connection with studies directed towards the synthesis of the pyranonaphthoquinone antibiotic medermycin, C-aryl glycosides were prepared by C-glycosylation of naphthols with glycosyl donors. Boron trifluoride diethyl etherate proved to be a suitable Lewis acid to promote the C-glycosylation, and use of the azido glycosyl donor proved more successful than using the dimethylamino glycosyl donor. 5-Hydroxy-1,4-dimethoxynaphthalene underwent facile C-glycosylation with two particular glycosyl donors, whereas 3-bromo-5-hydroxy-1,4-dimethoxynaphthalene was not an effective coupling partner with the same glycosyl donors. These studies indicate that subtle steric and electronic effects need to be considered in order to fine-tune C-glycosylations when using highly functionalized glycosyl donors.
The preparation of oxygenated naphthyl stannanes bearing an ortho-methoxy substituent is described, including stannanes (23) and (25) which are key intermediates for the synthesis of dimeric pyranonaphthoquinone antibiotics. Stannanes (17), (19) and (21)–(23) were obtained by metal–halogen exchange of the corresponding bromonaphthalenes. In an alternative approach to effect stannylation, a palladium(0)-mediated coupling reaction using hexaalkylditin reagents was examined. The Stille coupling reaction between naphthyl stannanes (23) and (25) and the corresponding bromonaphthalenes (11) and (24) failed to effect coupling to the desired binaphthyls.