HSQC

1. HSQC = Heteronuclear single-quantum coherence (Bodenhausen and Ruben, 1980) HSQC 1H 13C J evolution J evolution 13C evolution CHEM 991J Lecture 23 10/24/2011: HSQC/ coherence transfer tools 1H evolution coherence transfer coherence transfer Advantage: detection of 1H nuclei, which have larger dipole moments (detection at high frequency is also more efficient) ωI Note: 1H-1H couplings still present (also 13C-13C couplings if material is 13C enriched. ωS

2. Idq,x = Ix′Sx′ – Iy′Sy′ Izq,x = Ix′Sx′ + Iy′Sy′ Idq,y = Iy′Sx′ + Ix′Sy′ Izq,y = Iy′Sx′ – Ix′Sy′ coherence transfer modules Assume both phases y′: Ix′Sz → –IzSx′ Iy′Sz → Iy′Sx′ = ½(Izq,y + Idq,y) Idq,y → –Iy′Sz – IzSy′ Idq,x → IzSz – Iy′Sy = IzSz + ½(Idq,x – Izq,x) Izq,y → –Iy′Sz + IzSy′ Izq,x → IzSz + Iy′Sy′ = IzSz – ½(Idq,x – Izq,x) CHEM 991J Lecture 23 10/24/2011: HSQC/ coherence transfer tools Assume phase y′: Ix′Sz → Ix′Sx′ = ½(Izq,x + Idq,x) Iy′Sz → Iy′Sx′ = ½(Izq,y + Idq,y) Idq,y → –Iy′Sz + Ix′Sy = –Iy′Sz + ½(Idq,y – Izq,y) Idq,x → –Ix′Sz – Iy′Sy′ = –Ix′Sz + ½(Idq,x – Izq,x) Izq,y → –Iy′Sz – Ix′Sy′ = –Iy′Sz + ½(Izq,y – Idq,y) Izq,x → –Ix′Sz + Iy′Sy = –Ix′Sz – ½(Idq,x – Izq,x)