The photochemical reaction of 1,4-naphthalenedicarbonitrile with aromatic pinacols and pinacol ethers
作者:A. Albini、M. Mella
DOI:10.1016/s0040-4020(01)88083-2
日期:1986.1
Irradiation of 1,4-naphthalenedicarbonitrile (NDN) in deoxygenated acetonitrile in the presence of aromatic pinacols (1) leads to reduction of the former to the dihydro derivative 4 and the tetrahydro derivative 5 as well as to oxidative cleavage of the latter to yield ketones or aldehydes (3). Reaction with pinacol ethers (2) leads to product types 3, 4 and 5 as well as to 1(1-methoxybenzyl)-1,2-dihydro
在芳族pin草醇(1)存在下在脱氧乙腈中辐照1,4-萘二甲腈(NDN)导致前者还原为二氢衍生物4和四氢衍生物5,并导致后者的氧化裂解产生酮。或醛(3)。反应与频哪醇的醚(2)导致的产品类型3,4和5以及对1(1甲氧基苄基)-1,2-二氢NDN衍生物(二对映异构体,6和7)。这些加合物中只有一种是在NDN与苄基甲基醚的反应中形成的(8)。该反应涉及电子转移至单重激发的NDN并裂解自由基阳离子1 XXX和2 XXX,分别产生α-羟基和α-甲氧基。它们在第一种情况下通过质子转移与NDN反应,在后一种情况下通过碳-碳键形成而与NDN反应。在与8形成加合物时观察到的立体选择性是通过自由基阳离子的去质子化以及相应的自由基与双价溶剂笼中NDNXXX的反应来解释的。根据最近的快速光解研究讨论了这些反应的机理。