NOVELTY - A silacycloalkane (I) is prepared by: (1) adding a substituted silacycloalkane (II) to a suspension of lithium aluminum hydride in a glycol diether at greater than 50degreesC to form a mixture; and (2) distilling the mixture under reduced pressure at greater than 50degreesC to remove the silacycloalkane.    USE - The inventive method is for preparing a silacycloalkane. The produced silacycloalkane can be used as a coating on solar panels and as a precursor for synthesizing various sila drugs. It can be used to prepare polycarbosilanes, which are useful as ceramic precursors.    ADVANTAGE - The inventive method produces silacycloalkane having high purity in high yield. The silacycloalkane can be readily and efficiently removed from the reaction mixture by distillation. This separation minimizes the occurrence of unwanted side reactions that can diminish purity and yield. The silacycloalkane product is free of solvent, which can be deleterious in certain applications, particularly in the electronics field. Further, the inventive method can be carried out economically with a stoichiometric amount or only slight excess of lithium aluminum hydride. It can be scaled to a commercial manufacturing process.    DETAILED DESCRIPTION - Preparation of a silacycloalkane of formula (I), comprises:    (1) adding a substituted silacycloalkane of formula (II) to a suspension of lithium aluminum hydride in a glycol diether at greater than 50degreesC to form a mixture; and    (2) distilling the mixture under reduced pressure at greater than 50degreesC to remove the silacycloalkane.    The glycol diether contains a linear arrangement of oxyalkylene units having a formula: -OCH2CH2-, -OCH2CH(CH3)- or -OCH2CH(CH2CH3)-; and end-groups having the formulae -R2 and -OR2. It has a normal boiling point of at least 85degreesC, and a viscosity of not more than 3000 mm2/s at 25degreesC.    n = 1, 2, or 3;    X1 = -F, -Cl, -Br, or -OR1;    X2 = X1 or H;    R1 = 1-8C hydrocarbyl; and    R2 = 1-8C alkyl, Ph, or 1-8C alkyl substituted Ph.