The addition of the Grignard reagent to a carbonyl typically proceeds through a six-membered ring transition state.
ð ɪ WORD_BOUNDARY ʌ d ɪ ʃ ə n WORD_BOUNDARY ʌ v ð ə WORD_BOUNDARY ɡ ɹ ɪ ɡ n ɑ ɹ d WORD_BOUNDARY ɹ ɪ eɪ d̠ʒ ə n t WORD_BOUNDARY t ʊ WORD_BOUNDARY ʌ WORD_BOUNDARY k ɑ ɹ b ə n aɪ l WORD_BOUNDARY t ɪ p ɪ k l i WORD_BOUNDARY p ɹ oʊ s iː d z WORD_BOUNDARY θ ɹ uː WORD_BOUNDARY ʌ WORD_BOUNDARY s ɪ k s m ɛ m b ə ɹ d WORD_BOUNDARY ɹ ɪ ŋ WORD_BOUNDARY t ɹ æ n s ɪ ʃ ə n WORD_BOUNDARY s t eɪ t WORD_BOUNDARY