A convenient synthesis of unsymmetrical pinacols by coupling of structurally similar aromatic aldehydes mediated by low-valent titanium
The one-pot, selective cross pinacol-type couplings between two structurally similar aromatic aldehydes promoted by low-valent titanium generated unsymmetrical pinacols in moderate to good isolated yields in an erythrolthreo ratio of up to 91:9. This synt
Pinacol coupling reaction of aromatic aldehydes mediated by aqueous vanadium(II) solution under ultrasound irradiation
Pinacol coupling of aromatic aldehydes by aqueous vanadium(II) solution under ultrasound irradiation at room temperature can lead to the corresponding pinacols in 54-93% yields within 15-30 min. Copyright Taylor & Francis, Inc.
Wang, Shu-Xiang,Wang, Ke,Li, Ji-Tai
p. 2387 - 2394
(2007/10/03)
Reductive coupling of aromatic aldehydes to pinacols using active manganese under ultrasound irradiation
The pinacol coupling of aromatic aldehydes has been carried out in 30-98% yield with active manganese at r.t. for 2 hr under ultrasound irradiation. The main advantages of the present procedure are shorter reaction time, less reagent (manganese) and higher yield of pinacols.
Magnesium-induced pinacol coupling of aromatic aldehydes and ketones in water under ultrasound
The pinacol coupling of aromatic aldehydes and ketones has been carried out in 20-62% and 10-91% yields, respectively with Mg and Mg-MgCl2 in water under ultrasound irradiation at room temperature for 3-4hr.
Pinacol coupling of aromatic aldehydes using aluminium under ultrasound irradiation
The pinacol coupling reaction of aromatic aldehydes and ketones was carried out in 26-98% yield with Al in aqueous NaOH-MeOH under ultrasound irradiation at r.t. within 30 min.
Pinacol coupling of aromatic aldehydes and ketones using Zn-ZnCl2 under ultrasound
The coupling reaction of aromatic aldehydes and ketones leading to pinacols has been carried out using Zn-ZnCl2 in 50% aq. THF under ultrasound in 5-77% yield.