The cyclic tetrasiloxane is one of the fundamental raw materials of the silicone industry. For example, global manufacturers are producing large amount of octamethylcyclotetrasiloxane, namely D₄, as a building block in the production of silicone polymers or as an additive in personal care products. In spite of its importance in silicone engineering, only a few synthetic methods have been reported for stereoregular cyclic tetrasiloxanes.¹ The simplest cyclotetrasiloxanol, 1,3,5,7-tetrahydroxy-1,3,5,7-tetramethylcyclotetrasiloxane (MeD₄OH), has been interested due to its potentiall utility such as precursors to cage or ladder-type polysilsesquioxanes.² In this presentation we will show a facile synthetic pathway for stereoregular MeD₄OHs and their derivatives. References 1. (a) Endo, H.; Takeda, N.; Unno, M. Chem. Asian J. 2017, 12, 1224. (b) Kinoshita, S.; Watase, S.; Matsukawa, K. Kaneko, Y. J. Am. Chem. Soc. 2015, 137, 5061‒5065. (c) Pozdnyakova, Y. A.; Korlyukov, A. A.; Kononova, E. G.; Lyssenko, K. A.; Peregudov, A. S.; Shchegolikhina, O. I. Inorg. Chem. 2010, 49, 572‒577. (d) Shin, H. J.; Jeong, H. D. U.S. Patent 7,338,689, Mar. 4, 2008. (e) Suyama, K.-I.; Gunji, T.; Arimitsu, K.; Abe, Y. Organometallics 2006, 25, 5587‒5593. (g) Ito, R.; Kakihana, Y.; Kawakami, Y. Chem. Lett. 2009, 38, 364‒365. (f) Lee, H. S.; Choi, S.-S.; Baek, K.-Y.; Hong, S. M.; Lee, E. C.; Lee, J.-C.; Hwang, S. S. Eur. Polymer J. 2012, 48, 1073‒1081. 2. For reviews, see (a) Unno, M.; Suto, A.; Matsumoto, T. Russ. Chem. Rev. 2013, 82, 289‒302. (b) Cordes, D. B.; Lickiss, P. D.; Rataboul, F. Chem. Rev. 2010, 110, 2081‒2173.