TY - JOUR

T1 - Synthesis of coenzyme Q0 through divanadium-catalyzed oxidation of 3,4,5-trimethoxytoluene with hydrogen peroxide

AU - Zalomaeva, Olga V.

AU - Evtushok, Vasilii Yu

AU - Maksimov, Gennadii M.

AU - Maksimovskaya, Raisa I.

AU - Kholdeeva, Oxana A.

PY - 2017/4/28

Y1 - 2017/4/28

N2 - The selective oxidation of methoxy/methyl-substituted arenes to the corresponding benzoquinones has been first realized using aqueous hydrogen peroxide as a green oxidant, acid tetrabutylammonium salts of the γ-Keggin divanadium-substituted phosphotungstate [γ-PW10O38V2(μ-O)2]5- (I) as a catalyst, and MeCN as a solvent. The presence of the dioxovanadium core in the catalyst is crucial for the catalytic performance. The reaction requires an acid co-catalyst or, alternatively, a highly protonated form of I can be prepared and employed. The industrially relevant oxidation of 3,4,5-trimethoxytoluene gives 2,3-dimethoxy-5-methyl-1,4-benzoquinone (ubiquinone 0 or coenzyme Q0, the key intermediate for coenzyme Q10 and other essential biologically active compounds) with 73% selectivity at 76% arene conversion. The catalyst retains its structure under turnover conditions and can be easily recycled and reused without significant loss of activity and selectivity.

AB - The selective oxidation of methoxy/methyl-substituted arenes to the corresponding benzoquinones has been first realized using aqueous hydrogen peroxide as a green oxidant, acid tetrabutylammonium salts of the γ-Keggin divanadium-substituted phosphotungstate [γ-PW10O38V2(μ-O)2]5- (I) as a catalyst, and MeCN as a solvent. The presence of the dioxovanadium core in the catalyst is crucial for the catalytic performance. The reaction requires an acid co-catalyst or, alternatively, a highly protonated form of I can be prepared and employed. The industrially relevant oxidation of 3,4,5-trimethoxytoluene gives 2,3-dimethoxy-5-methyl-1,4-benzoquinone (ubiquinone 0 or coenzyme Q0, the key intermediate for coenzyme Q10 and other essential biologically active compounds) with 73% selectivity at 76% arene conversion. The catalyst retains its structure under turnover conditions and can be easily recycled and reused without significant loss of activity and selectivity.

KW - SELECTIVE OXIDATION

KW - P-BENZOQUINONES

KW - PHENOLS

KW - TRIMETHOXYBENZENES

KW - METHOXYBENZENES

KW - METHOXYARENES

KW - HYDROXYLATION

KW - QUINONE

UR - http://www.scopus.com/inward/record.url?scp=85018466312&partnerID=8YFLogxK

U2 - 10.1039/c7dt00552k

DO - 10.1039/c7dt00552k

M3 - Article

AN - SCOPUS:85018466312

VL - 46

SP - 5202

EP - 5209

JO - Dalton Transactions

JF - Dalton Transactions

SN - 1477-9226

IS - 16

ER -