Five-membered ring spiro-annulation via thermal rearrangement of enol silyl ethers of 2-(cyclopropylmethylene) cycloalkanones. A formal total synthesis of some …

~10%

~%

~%

~44%

~%

~%

~%

~28%

~%

~26%

~%

~%

~%

~%

~%

~%

~%

~%

~%

~%