Photocatalytic redox-combined synthesis of l-pipecolinic acid with a titania-modified microchannel chip

Abstract A titania-modified microchannel chip (TMC) was fabricated to implement an efficient photocatalytic synthesis of l -pipecolinic acid from l -lysine. The conversion rate in the chip was 70 times larger than that in a cuvette using nm-sized titania particles with almost the same selectivity and enantiomeric excess. The results showed that TMC had satisfactory potential to allow its application to photocatalytic synthesis as well as photodegradation.

[1]  Takehiko Kitamori,et al.  A Microfluidic Device for Conducting Gas-Liquid-Solid Hydrogenation Reactions , 2004, Science.

[2]  Eiichi Kojima,et al.  Light-induced amphiphilic surfaces , 1997, Nature.

[3]  B. Ohtani,et al.  Photocatalytic one-step syntheses of cyclic imino acids by aqueous semiconductor suspensions , 1990 .

[4]  T. Kitamori,et al.  Spectroelectrochemical detection using thermal lens microscopy with a glass-substrate microelectrode-microchannel chip , 2005 .

[5]  Paul Watts,et al.  Micro reactors: principles and applications in organic synthesis , 2002 .

[6]  Takehiko Kitamori,et al.  Chemicofunctional membrane for integrated chemical processes on a microchip. , 2003, Analytical chemistry.

[7]  Klavs F. Jensen,et al.  Microfabricated multiphase packed-bed reactors : Characterization of mass transfer and reactions , 2001 .

[8]  Roger Gorges,et al.  Photocatalysis in microreactors , 2004 .

[9]  N G Wilson,et al.  Microfabricated reactors for on-chip heterogeneous catalysis. , 2001, The Analyst.

[10]  M. Northrup Micro Total Analysis Systems 2003 , 2003 .

[11]  B. Ohtani,et al.  Photocatalytic redox-combined synthesis of l-pipecolinic acid from l-lysine by suspended titania particles: effect of noble metal loading on the selectivity and optical purity of the product , 2003 .

[12]  S. Hotchandani,et al.  Electrochemically assisted photocatalysis: titania particulate film electrodes for photocatalytic degradation of 4-chlorophenol , 1993 .

[13]  Takehiko Kitamori,et al.  Stabilization of liquid interface and control of two-phase confluence and separation in glass microchips by utilizing octadecylsilane modification of microchannels. , 2002, Analytical chemistry.