N,O-bidentate Directing Group Assisted Ortho-C-H Functionalization Of Benzyl Alcohols

Recently,In order to meet the inherent requirements of green chemistry,transition-metal-catalyzed C-H functionalization reaction has become an important area in organic chemistry.C-H functionalization reaction not only shorted the experimental procedure,but also does not require pre-functionalized substrates.Therefore,highly regioselective functionalization of a C-H bond to construct complex organic molecules is becoming an important and attractive process in synthetic chemistry.In this thesis,we are focused on the development a new directing group to realize the ortho-C-H functionalization of benzyl alcohols and phenyl ethylalcohols via the palladium catalyst.A wide variety functionalized aromatic alkylalcohols has been achieved in a direct approach.The first chapter briefly introduced the development of C-H functionalization over the past year.Firstly,a short summary of transition-metal-catalyzd C-N bond formation reaction has been discussed;Secondly,the direct C-H alkynylation has been well introduced in regarding to the alkynylation reagents;Thirdly,the directing assisted C-H bond activation of alcohols have been well summarized.In the second chapter,a convenient protocol for the synthesis of o-aminobenzaldehyde and benzoxazole derivatives by modifying the oxidant has been well explored.a high atom efficiency one-pot,two-step approach to form quinazolines from benzyl alcohol derivatives has been achieved in good yields,thus demonstrating its high utility.In the third chapter,the N,N-dimethyl)oxalamide assisted direct alkynylation of benzyl alcohol derivatives has been disclosed.Various functional groups are tolerated,affording the corresponding alkynylated products in moderate to good yields.