Arp Fabian F, Ashirov Rahym, Bhuvanesh Nattamai, Blümel Janet
Department of Chemistry, Texas A&M University, College Station, TX, 77842-3012, USA.
Dalton Trans. 2021 Nov 2;50(42):15296-15309. doi: 10.1039/d1dt03243g.
The di(hydroperoxy)adamantane adducts of water (1) and phosphine oxides -TolPO·(HOO)C(CH) (2), -TolPO·(HOO)C(CH) (3), and CyPO·(HOO)C(CH) (4), as well as a CHCl adduct of a phosphole oxide dimer (8), have been created and investigated by multinuclear NMR spectroscopy, and by Raman and IR spectroscopy. The single crystal X-ray structures for 1-4 and 8 are reported. The IR and P NMR data are in accordance with strong hydrogen bonding of the di(hydroperoxy)adamantane adducts. The Raman (O-O) stretching bands of 1-4 prove that the peroxo groups are present in the solids. Selected di(hydroperoxy)alkane adducts, in combination with AlCl as catalyst, have been applied for the direct oxidative esterification of -nonyl aldehyde, benzaldehyde, -methylbenzaldehyde, -bromobenzaldehyde, and -hydroxybenzaldehyde to the corresponding methyl esters. The esterification takes place in an inert atmosphere, under anhydrous and oxygen-free conditions, within a time frame of 45 minutes to 5 hours at room temperature. Hereby, two oxygen atoms per adduct assembly are active with respect to the quantitative transformation of the aldehyde into the ester.
水（1）和氧化膦——甲苯基氧化膦·(HOO)C(CH) （2）、甲苯基氧化膦·(HOO)C(CH) （3）以及环己基氧化膦·(HOO)C(CH) （4）的二（氢过氧）金刚烷加合物，还有氧化膦二聚体的CHCl加合物（8），已通过多核核磁共振光谱、拉曼光谱和红外光谱进行了制备与研究。报道了1 - 4和8的单晶X射线结构。红外光谱和磷核磁共振数据与二（氢过氧）金刚烷加合物的强氢键作用相符。1 - 4的拉曼（O - O）伸缩带证明过氧基团存在于固体中。选定的二（氢过氧）烷加合物与AlCl作为催化剂相结合，已用于将壬醛、苯甲醛、对甲基苯甲醛、对溴苯甲醛和对羟基苯甲醛直接氧化酯化生成相应的甲酯。酯化反应在惰性气氛、无水无氧条件下于室温45分钟至5小时内进行。由此，每个加合物组件中的两个氧原子对于醛定量转化为酯具有活性。
