((TRITYLOXY)METHYL)BORONIC ESTERS

被引：33

作者：

HO, OC ^{[1
]}

SOUNDARARAJAN, R ^{[1
]}

LU, JH ^{[1
]}

MATTESON, DS ^{[1
]}

WANG, ZM ^{[1
]}

CHEN, X ^{[1
]}

WEI, MY ^{[1
]}

WILLETT, RD ^{[1
]}

机构：

[1] WASHINGTON STATE UNIV,DEPT CHEM,PULLMAN,WA 99164

来源：

ORGANOMETALLICS | 1995年 / 14卷 / 06期

关键词：

D O I：

10.1021/om00006a034

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Sodium trityl oxide with 2-(bromomethyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane [pinacol (bromomethyl)boronate (1)] in dimethyl sulfoxide efficiently yields 4,4,5,5-tetramethyl-2-[(triphenylmethoxy)methyl]-1,3,2-dioxaborolane (3), which can be transesterified with chiral diols to form other [(triphenylmethoxy)methyl]-1,3,2-dioxaborolanes. These can undergo chain extension with (dichloromethyl)lithium in the normal manner and are potentially useful synthetic intermediates. The majority of known boronic esters are liquids, but the trityl group confers crystallinity on several examples. Six structures have been determined: 4,4,5,5-tetramethyl-2-[(triphenylmethoxy)methyl]-1,3,2-dioxaborolane (3), [R-(4 alpha,5 beta)]-4,5-dicyclohexyl-2-[(triphenylmethoxy)methyl] (4), [S-(4 alpha,5 beta)]-4,5-bis(1-methylethyl)-2-[(triphenylmethoxy)methyl]-1,3,2-dioxaborolane (5), (R)-pinanediol ((trityloxy)methyl)boronate (ent-6), (S)-pinanediol (S)-(1-chloro-2-(trityloxy)ethyl)boronate (7a), and (S)-pinanediol (S)-(1-bromo-2-(trityloxy)ethyl)boronate (7b). The 1,3,2-dioxaborolane ring is very nearly planar, consistent with strong oxygen-boron pi-bonding.

引用

页码：2855 / 2860

页数：6

共 31 条

[1] The spontaneous dissociation of triphenylmethyl disulfide with the formation of triphenylmethyl the potassium derivative of triphenyl carbinol and its use as a synthetic agent [J].