ate ▁with ▁p all ad ium ▁catal yst s ▁is ▁shown ▁below . ▁ ▁Sp 2 - hy brid ized ▁carbon ▁groups ▁attached ▁to ▁tin ▁are ▁the ▁most ▁commonly ▁used ▁coupling ▁partners , ▁and ▁sp 3 - hy brid ized ▁car b ons ▁require ▁har sh er ▁conditions ▁and ▁terminal ▁alk yn es ▁may ▁be ▁couple d ▁via ▁a ▁C - H ▁bond ▁through ▁the ▁Son og ash ira ▁reaction . ▁ ▁As ▁the ▁organ ic ▁tin ▁comp ound , ▁a ▁trim eth yl st ann yl ▁or ▁trib ut yl st ann yl ▁comp ound ▁is ▁normally ▁used . ▁Although ▁trim eth yl st ann yl ▁comp ounds ▁show ▁higher ▁react ivity ▁compared ▁with ▁trib ut yl st ann yl ▁comp ounds ▁and ▁have ▁much ▁simpler ▁ 1 H - N MR ▁spect ra , ▁the ▁to x icity ▁of ▁the ▁former ▁is ▁much ▁larger . ▁ ▁However , ▁the ▁most ▁w ides p read ▁use ▁of ▁the ▁St ille ▁reaction ▁is ▁its ▁use ▁in ▁organ ic ▁synth eses , ▁and ▁specifically , ▁in ▁the ▁synth esis ▁of ▁natural ▁products . ▁ ▁Natural ▁Product ▁Total ▁Syn thesis ▁ ▁Over man ' s ▁ 1 9 - step ▁en ant io select ive ▁total ▁synth esis ▁of ▁quadr ig em ine ▁C ▁involves ▁a ▁double ▁St ille ▁cross ▁met ath esis ▁reaction . ▁ ▁The ▁complex ▁organ ost ann ane ▁is ▁couple d ▁onto ▁two ▁ar yl ▁i od ide ▁groups . ▁ ▁After ▁a ▁double ▁He ck ▁cycl ization , ▁the ▁product